Zodiac Killer

The Zodiac Killer is the pseudonym of an unidentified serial killer who operated in Northern California in the late 1960s. The Zodiac murdered five known victims in the San Francisco Bay Area between December 1968 and October 1969, operating in rural, urban and suburban settings. He targeted three young couples and a lone male cab driver. The case has been described as "arguably the most famous unsolved murder case in American history", and has become both a fixture of popular culture and a focus for efforts by amateur detectives.

The Zodiac's known attacks took place in Benicia, Vallejo, unincorporated Napa County, and the city of San Francisco proper. Of his seven wounded victims, two survived. He coined his name in a series of taunting messages that he mailed to regional newspapers, in which he threatened killing sprees and bombings if they were not printed. Some of the letters included cryptograms, or ciphers, in which the killer claimed that he was collecting his victims as slaves for the afterlife. Of the four ciphers he produced, two remain unsolved, while the others were cracked in 1969 and 2020.

The last confirmed Zodiac letter was in 1974, when he claimed to have killed 37 victims. He claimed many of them were in Southern California, including Cheri Jo Bates, who was murdered in Riverside in 1966; a connection between the two has not been proven. While many theories regarding the identity of the Zodiac have been suggested, the only suspect authorities ever publicly named was Arthur Leigh Allen, a former elementary school teacher and convicted sex offender who died in 1992.

The unusual nature of the case led to international interest that has been sustained throughout the years. The San Francisco Police Department marked the case "inactive" in 2004, but re-opened it at some point prior to 2007. The case also remains open in the California Department of Justice, Federal Bureau of Investigation, the city of Vallejo, as well as in Napa and Solano counties.

Confirmed attacks
The Zodiac Killer claimed in messages to newspapers to have committed thirty-seven serial murders. Investigators agree on seven confirmed assault victims, five of whom died and two of whom survived:
 * David Arthur Faraday (17) and Betty Lou Jensen (16) were shot and killed on December 20, 1968, on Lake Herman Road, within the city limits of Benicia, California.
 * Michael Renault Mageau (19) and Darlene Elizabeth Ferrin (22) were shot around midnight between July 4 and 5, 1969, in the parking lot of Blue Rock Springs Park in Vallejo, California. Mageau survived the attack; Ferrin was pronounced dead on arrival at Kaiser Foundation Hospital.
 * Bryan Calvin Hartnell (20) and Cecelia Ann Shepard (22) were stabbed on September 27, 1969, at Lake Berryessa in Napa County, California. Hartnell survived, but Shepard died as a result of her injuries on September 29.
 * Paul Lee Stine (29) was shot and killed on October 11, 1969, in the Presidio Heights neighborhood of San Francisco.

Lake Herman Road murders
The first murders widely attributed to the Zodiac were the shootings of high school students Betty Lou Jensen and David Arthur Faraday on December 20, 1968. Jensen was a 16-year old student at Hogan High School, and on the night of the 20th she had a date with Faraday, a 17-year old student from the neighboring Vallejo High School. Faraday drove his mother's car to Jensen's house at 8 p.m., and they left in the car at 8:30, driving to the house of one of Jensen's friends. Sometime after 9, they drove to the outskirts of Vallejo, and parked at a lover's lane on Lake Herman Road. A passing motorist noticed the couple between 10:15 to 10:30, parked on the side of Lake Herman Road, on a gravel runoff near the gate to a water pumping station. They were spotted again at 11.

The couple were attacked sometime between 11:05 and 11:10. Police determined that an unknown assailant pulled his car up next to Faraday's, about 10 feet away from the passenger's side of the vehicle. He left his vehicle and approached the couple's car, firing several shots inside. The bullets hit various car parts, but not the couple; he may have been trying to force them to leave the vehicle. They both attempted to leave through the passenger door. Jensen was able to get out. As Faraday was leaving, the assailant shot him in the head with a .22-caliber rifle. The assailant began to chase Jensen, who was running away. He fired six shots at her, hitting her in the back five times. He then left in his vehicle. The police theorized the whole attack took two to three minutes.

A passing motorist spotted the couple's bodies at 11:10. She drove down the road and flagged a police patrol car to report the scene. The officers in the car immediately went to the scene. Jensen was pronounced dead, and Faraday was still breathing. He was taken to the hospital, but died from his wounds. Police could find no usable tire or foot prints of the assailant, and there were no witnesses. They were unable to find a motive other than the killer being a "madman". An intensive investigation took place over the following months, but a viable suspect was never developed. The murders were extensively covered by the media. For seven months afterwards, the Zodiac Killer is not confirmed to be active. Author Michael Kelleher and David Van Nuys suggest this was a "cooling off period" to reflect on his actions, experienced by most serial killers.

Background
The couple Darlene Ferrin and Michael Mageau were shot around midnight between July 4 and 5, 1969. Ferrin was fatally wounded, and Mageau survived. Ferrin was 22, and was popular with many in the community due to her job at a local restaurant. There, she met Michael Mageau, who was 19. They became friends, and went on a date on July 4, despite the fact that Ferrin was still married to Dean Ferrin. After 11:30 p.m. that night, Ferrin received a phone call in her house, probably from Mageau. She left and arrived at Mageau's house around 11:50.

Afterwards, the facts in the case become "clouded with conflicting statements and speculation". Some information comes from Zodiac researcher Robert Graysmith's work. Allegedly, immediately after Ferrin and Mageau left the house, they started believing or noticed that they were being followed by a man in a light-colored car. For some reason, Darlene started driving out of town in the direction of Lake Herman Road. Shortly before midnight, she turned her car into an empty parking lot of Blue Rock Springs Park. It was another popular area for couples, two miles from Lake Herman Road. She parked 70 feet from the lot entrance, and soon, another vehicle parked around 80 feet to her left. The unknown driver, a man, turned the headlights off and sat motionless at the steering wheel. Mageau asked who the driver was, and Ferrin vaguely replied to not be worried about it. The driver then left the parking lot, likely at a high speed.

Shooting
Five minutes later, the driver returned, and parked a few feet next to Ferrin's vehicle at the passenger's side. He exited his car, and approached Ferrin's. The man shone a flashlight into the car; the couple assumed he was a police officer and rolled down the window. The man did not speak, and fired a gun into the car. One bullet hit Mageau in the right arm, and the other hit Ferrin in the neck, causing her to slump towards the steering wheel and become motionless. Mageau tried to leave the car, but the door handle on the passenger's side was missing or removed. The assailant stepped away from Ferrin's car, and went back to his own. He did not immediately leave, but instead opened his car door and did something Mageau could not see. He looked back at Mageau, struggling to get out of Ferrin's car, and moved quickly back to him. Four more shots were fired, two at each person. The attacker moved quickly back to his car and drove off. The attacker was heard by the golf course's caretaker, who estimated it to be at 12:10 a.m. The killer left no clues that could be traced back to him.

Aftermath
Soon, three teenagers drove into the parking lot and saw the wounded couple. They left to get help, and police arrived at the scene at 12:20. The couple were taken to the hospital. Mageau survived, but Ferrin was pronounced dead at 12:40. Mageau described the killer as a white man with a large face, who was heavyset, around 5 feet 8 inches tall, weighed 195 to 200 pounds, and had short, curly light brown hair and a potbelly. He was wearing dark clothes and did not have glasses. These details were not enough to develop a suspect. Moments after 12:40, the Vallejo Police Department received a phone call from a public telephone within two blocks from them. The man on the other end of the line stated: "I want to report a double murder. If you go one mile east on Columbus Parkway to the public park you will find kids in a brown car. They were shot with a 9-millimeter Luger. I also killed those kids last year. Goodbye."

Ferrin-Zodiac prior relationship theories
Controversy surrounds the discussion of whether or not Ferrin knew the Zodiac Killer beforehand. Kelleher and Nuys write that theories regarding a potential relationship started with Robert Graysmith's book Zodiac. He argued extensively for a connection, using events he was told by Ferrin's friends. However, the argument was ultimately based on "speculation and assumption". There has been no proven connection. At the hospital, Mageau said he did not know the attacker, and different sources state that he said he was unsure if Ferrin knew him, or that Ferrin did know him, and his name was Richard. Ferrin's sister also claims one of Darlene's boyfriends was named Richard. In the Zodiac's later correspondence, he only ever referred to Ferrin with the term "girl". The locations of the Zodiac's three known shootings could imply he only shot Ferrin and Mageau because of their isolated location. Kelleher and Nuys focus on the idea that the couple were followed once they left Mageau's house, which would be a clue towards the killer knowing Ferrin. One version of events describes a high speed chase between the unknown driver and Ferrin, which would make it unlikely for her to drive into the deserted parking lot instead of getting help. There is also suspicion as to why, if they were being followed into the lot, Ferrin did not drive out of it once the unknown driver initially left. Kelleher and Nuys suggest that Ferrin telling Mageau not to worry about the driver, and the couple assuming he was a police officer, are more likely to happen if they arrived on their own accord.

In 2010, a picture surfaced of Ferrin and an unknown man who closely resembles the composite sketch of the Zodiac. In a 2011 episode of America's Most Wanted, police stated they believe the photo was taken in San Francisco in either 1966 or 1967. Ferrin did know Betty Lou Jensen and David Faraday. She previously attended Hogan High School, was familiar with Lake Herman Road's status as a lover's lane, and lived less than two blocks from Jensen's house.

First letters from the Zodiac
The Zodiac's letters, sent at least from 1969 to 1974, often started with "This is the Zodiac speaking" and signed with a symbol resembling the crosshairs of a gunsight:. He sent out four cryptograms, or ciphers; two have been solved, one in 1969 and one in 2020. The letters were postmarked San Francisco, except for the March 13, 1971 letter, which was postmarked Pleasanton. His use of astrological symbols led the police to "pore over occult works and astrological charts and even to consult psychics".

On August 1, 1969, three letters purportedly prepared by the killer were received at the Vallejo Times-Herald, the San Francisco Chronicle, and the San Francisco Examiner. The nearly identical letters, subsequently described by a psychiatrist to have been written by "someone you would expect to be brooding and isolated", took credit for the shootings at Lake Herman Road and Blue Rock Springs. He explained that he was killing victims to collect them as his personal slaves in the afterlife.

Each letter also included one-third of a 408-symbol cryptogram which the killer claimed contained his identity. The killer demanded they be printed on each paper's front page, or else he would "cruse [sic] around all weekend killing lone people in the night then move on to kill again, until I end up with a dozen people over the weekend." The Chronicle published its third of the cryptogram on page four of the next day's edition. An article printed alongside the code quoted Vallejo Police Chief Jack E. Stiltz as saying, "We're not satisfied that the letter was written by the murderer" and requested the writer send a second letter with more facts to prove his identity.

On August 4, the Examiner received a letter with the salutation, "Dear Editor This is the Zodiac speaking." This was the first time the killer had used this name for identification. The letter responded to Stiltz's request for the killer's personal information. He included details about the murders the public had not yet heard, and said that when the police cracked his code, "they will have me".

The Federal Bureau of Investigation (FBI) and Central Intelligence Agency (CIA) attempted to decode the 408-symbol cryptogram. However, on the 5th, it was cracked by Donald and Bettye Harden, a couple in Salinas. It contained a misspelled message in which the killer seemed to reference "The Most Dangerous Game", a 1924 short story by Richard Connell. The author also said that he was committing the killings in order to collect slaves for his afterlife. No name appears in this decoded text. The killer said that he would not give away his identity because it would slow down or stop his slave collection.

Lake Berryessa murder
On September 27, Pacific Union College students Bryan Hartnell and Cecelia Shepard were picnicking at Lake Berryessa on a small island connected by a sand spit to Twin Oak Ridge. A white male, about 5 ft weighing more than 170 lbs, approached the couple wearing a black executioner's-type hood with clip-on sunglasses over the eyeholes and a bib-like device on his chest that had a white 3 x 3 in cross-circle symbol on it. The hooded man approached with a gun, which Hartnell believed to be a .45, and claimed to be an escaped convict from a jail with a two-word name, in either Colorado or Montana, where he had killed a guard and subsequently stolen a car. A police officer later inferred that the man had been referring to a jail in Deer Lodge, Montana, yet a park ranger claimed that Hartnell told him the man referenced Colorado. The hooded man then said that he needed their car and money to travel to Mexico because the stolen vehicle was "too hot".

The killer had brought precut lengths of plastic clothesline and told Shepard to tie up Hartnell before the killer did the same with her. The killer checked, and tightened Hartnell's bonds after discovering that Shepard had bound them loosely. Hartnell initially believed this event to be a bizarre robbery, but the man drew a knife and stabbed them both repeatedly. Hartnell suffered six wounds and Shepard ten in the process. The killer then hiked 500 yd up to Knoxville Road, drew the cross-circle symbol on Hartnell's car door with a black felt-tip pen, and wrote beneath it:

At 7:40 p.m., the killer called the Napa County Sheriff's Department from a pay telephone at a car wash in downtown Napa. The caller first stated to the operator that he wished to "report a murder – no, a double murder", before saying that he had committed the crime. KVON radio reporter Pat Stanley found the phone, still off the hook, a few minutes later. The phone was located a few blocks from the sheriff's office, and 27 mi from the crime scene. Detectives lifted a still-wet palm print from the phone but were never able to match it to any suspect.

After hearing the victims' screams for help, a man and his son fishing in a nearby cove discovered Hartnell and Shepard and got help by contacting park rangers. Napa County deputies Dave Collins and Ray Land were the first law enforcement officers to arrive at the crime scene. Shepard was conscious when Collins arrived and provided him a detailed description of the attacker. She and Hartnell were taken to Queen of the Valley Hospital in Napa by ambulance. Shepard lapsed into a coma during transport, never regained consciousness, and died in the hospital two days later. Hartnell survived to recount his tale to the press. Napa County detective Ken Narlow, who was assigned to the case from the outset, worked on solving the crime until his retirement from the department in 1987.

Shooting
Two weeks later, at around 9:40 p.m. on October 11, a white male passenger, the Zodiac, entered the taxi driven by Paul Stine in downtown San Francisco, requesting to be driven to Washington and Maple streets in Presidio Heights. When they arrived, the passenger asked to be driven one block down to Washington and Cherry streets. The reason for the request is unknown; perhaps the Zodiac saw someone close by, or wanted to drive to the next block's corner, which was darker and obscured by a large tree. Stine then drove the distance. At approximately 9:55 p.m., the Zodiac shot Stine in the head with a handgun, likely killing Stine immediately. The Zodiac then took Stine's wallet and car keys. This was the last officially confirmed murder by the Zodiac.

Three teenagers across the street witnessed the incident and phoned the San Francisco Police Department (SFPD) while the crime was in progress, saying the man in question was a "husky" white man wearing a "dark or black jacket". The dispatcher mistakenly broadcast to police that the suspect was a Black man. The witnesses also observed the killer wiping the cab down and seemingly "rifling through the man's clothing". As he leaned on the inside of the cab and cleaned it up, he left partial prints from two of his right hand's fingers.

Two blocks from the crime scene, patrol officers responded to the radio dispatch and arrived to Washington and Cherry two minutes after the phone call was placed. They observed a white male in dark clothes walking north, away from the crime scene and towards the Presidio Army Base. This man may have been the Zodiac. When the officers' patrol car pulled up alongside the man, they asked him if he had seen anything suspicious. He responded that he had seen a man waving a gun earlier, and went east down Washington. They drove quickly away, believing that a Black man was the culprit.

Aftermath
Moments later, when more police arrived at the scene, Stine was declared dead and a search began of the nearby area, including the Presidio. The Zodiac had likely escaped by that point, getting into a parked car and driving across the Golden Gate Bridge.

The Stine murder was initially believed to be a routine robbery that had escalated into homicidal violence. However, on October 13, the Chronicle received a new letter from the Zodiac that claimed credit for the killing and contained a torn section of Stine's bloody shirt as proof. The letter also included a threat about killing schoolchildren on a school bus. In response, Bay Area police departments began escorting school buses. The officers who initially responded realized a few days after the murder they had seen the Zodiac, and a few days later they helped make a composite sketch of the man, alongside the teenage witnesses. SFPD detectives Bill Armstrong and Dave Toschi were assigned to the case.

A.M. San Francisco interview
At 2:00 a.m. on October 22, 1969, someone claiming to be the Zodiac called the Oakland Police Department (OPD), demanding that one of two prominent lawyers, F. Lee Bailey or Melvin Belli, appear that morning on A.M. San Francisco, a talk show on KGO-TV hosted by Jim Dunbar. Bailey was not available, but Belli agreed to appear. Dunbar appealed to the viewers to keep the lines open. Someone claiming to be the Zodiac called several times, and Belli asked the caller for a less ominous name and the caller picked "Sam". The caller said he would not reveal his true identity as he was afraid of being sent to the gas chamber (then California's capital punishment method). Belli arranged a rendezvous to meet the caller outside a shop on Mission Street in Daly City, but no one arrived. The call was later traced back to a mental patient named Eric Weill, who investigators concluded was not the Zodiac.

November 1969 letter and card
On November 8, the Zodiac mailed a card with another cryptogram consisting of 340 characters. This cipher, dubbed "Z-340", remained unsolved for over fifty-one years. On December 5, 2020, it was deciphered by an international team of private citizens, including American software engineer David Oranchak, Australian mathematician Sam Blake and Belgian programmer Jarl Van Eycke. In the decrypted message, the Zodiac denied being the "Sam" who spoke on A.M. San Francisco, explaining that he was not afraid of the gas chamber "because it will send me to paradice [sic] all the sooner". The team submitted their findings to the FBI, which verified the discovery, and stated that the decoded message gave no further clues to the identity of Zodiac.

On November 9, the Zodiac mailed a seven-page letter stating that two policemen stopped and actually spoke with him three minutes after he had shot Stine. The letter also said that the he would blow up a school bus, and claimed that the police would never catch him, because "I have been to clever for them" [sic]. Excerpts from the letter were published in the Chronicle on November 12, including the Zodiac's claim. That same day, Fouke wrote a memo explaining what had happened on the night of Stine's murder. On December 20, exactly one year after the Lake Herman Road murders, the Zodiac mailed a letter to Belli that included another swatch of Stine's shirt; the Zodiac said that he wanted Belli to help him.

Suspected victims
There is no consensus on the number of victims that the Zodiac had or the length of his criminal spree. In Zodiac, Robert Graysmith published a list attributing forty-nine victims to the Zodiac. Various other authors speculated at the time of the killings that several other high-profile murders and attacks may have been the work of the Zodiac, but none have been confirmed:

Raymond Davis
Local historian Kristi Hawthorne suggests that the Zodiac may have murdered 29-year-old cab driver Raymond Davis in Oceanside, California, on April 10, 1962. Following Hawthorne's research, Oceanside police announced that they were looking into possible connections between the Davis murder and the Zodiac. The day before the murder, an individual believed to be the culprit had phoned the Oceanside police and told them, "I am going to pull something here in Oceanside and you'll never be able to figure it out."

At 11:10 p.m. on the 10th, Davis radioed in to his dispatcher that he was taking a fare to South Oceanside. The next day, his body was found in an alley between the current and former mayors' houses by a police officer. Days later, before the April 9 call was publicly reported, the police received another call from someone who is presumed to be the same individual, saying: “Do you remember me calling you last week and telling you that I was going to pull a real baffling crime? I killed the cab driver and I am going to get me a bus driver next.” Nothing similar had happened in Oceanside before; police reacted to the murder by "putting armed guards on city buses and armed military police on buses heading to Camp Pendleton". There are similarities to the Zodiac murders: ABC10 wrote, "both cases involved attacks on cab drivers in wealthy neighborhoods, threats against buses, and cryptic messages expressly aimed at baffling investigators." The ammo used to kill Davis was from a .22 caliber pistol, the same as in the Lake Herman Road murders and the Lake Berryessa murders.

Robert George Domingos and Linda Faye Edwards
The Santa Barbara County Sheriff's Department claimed in a 1972 press release that the 1963 murders of a young couple in the county were the work of the Zodiac: “Although the anticipated response to this statement would be one of skepticism, let me say that we do not make this assertion frivolously". On June 4, 1963, 18-year-old Robert George Domingos and his fiancée, 17-year-old Linda Faye Edwards, were shot dead on a beach in Gaviota State Park, having skipped school at Lompoc High School that day for Senior Ditch Day.

Police believed that the assailant attempted to bind the victims, but when they freed themselves and attempted to flee, the killer shot them repeatedly in the back and chest. The weapon a .22 caliber semi-automatic firearm, probably a rifle, the same caliber of weapon used in the Lake Herman Road murders. The ammunition used, "Winchester Western Super X copper-coated bullets", was also used by the Zodiac. Pre-cut rope was used to bind the victims, just as in the Lake Berryessa attacks. The killer then placed their bodies in a small shack and then tried, unsuccessfully, to burn the structure to the ground. Dr. John Averitt, a police sergeant, clinical psychologist, and classmate of Domingos and Edwards, said, “I believe the murders were the work of the Zodiac killer, but I can’t prove it".

At mid-afternoon on June 2, a sniper had fired two shots at a group of teenagers at Tajiguas, located east of the Domingos and Edwards murders. None of them were hit, and they identified the shots as coming from a .22 caliber weapon. Earlier that April, a Santa Barbara store sold .22 ammunition from the same lot number as the Domingos and Edwards murders, the second place that ammunition in the country was found from that lot number besides Vandenberg Air Force Base. An investigation on the person(s) who bought the ammunition were done at the store and air base.

Johnny Ray Swindle and Joyce Ann Swindle
On February 5, 1964, Johnny Ray Swindle and Joyce Ann Swindle (both aged 19), a newlywed couple from Alabama, were gunned down while walking along Ocean Beach in San Diego while on their honeymoon. Their killer, who was on a nearby cliff with a .22 caliber long rifle, shot them from the cliff five times, then went down to them to shoot them both once in the head. Johnny was shot behind the ear, similar to the Zodiac murders. Despite multiple bullet wounds, Johnny remained alive for hours. Joyce died almost instantly after she was shot in the back, left arm and head. The suspect took Johnny's wallet and watch, then left the crime scene. The watch taken was a Timex, the same brand found at the Cheri Jo Bates murder (see below). The watch found at the Bates scene was initially assumed to belong to her murderer. Johnny died in the hospital that night.

Johnny's mother said she could not think of him having any enemies. Police speculated that the two were victims of a "thrill killer" and Rita, Johnny's sister, has theorized that the murders might have been the work of the Zodiac. They also believed there was a link to the Domingos and Edwards murders; author Soren Korsgaard notes how in both the Santa Barbara and Ocean Beach killings, the victims were shot from a distance, then the killer went down, reloaded, and shot them again. Both the Ocean Beach and Lake Herman Road murders used a .22 Remington Arms Model 550-1 rifle, but the ballistics did not match between the cartridges found at the two scenes. People who were suspected by police were a 51-year-old man living in a beach shack, a teenager alleged by a priest to be violent, and a 19-year-old Marine from San Diego who killed his parents and sister in Illinois. There were also two men who took interest in Joyce's necklace while her family was traveling to California; the necklace was taken from her at the crime scene.

Researcher Howard Davis theorizes the Zodiac left a hint towards having victims in San Diego, when, in 1969, he sent a page from an astrology magazine which read "Watch; want Zodiac, hidden magic amulet, flyt 555 birds fly south". A reporter who talked to Davis claimed that at some point, a United Flight 555 had a daily commute to San Diego. Birds could refer to planes, or in British English, girls. The locations of the Lake Berryessa, Santa Barbara, and Ocean Beach killings, if they are all done by the Zodiac, could mean his murders have some connection to water.

Cheri Jo Bates
On October 30, 1966, Cheri Jo Bates, an 18-year-old student at Riverside City College (RCC), spent the evening at the campus library annex until it closed at 9:00 p.m. Neighbors reported hearing a scream around 10:30. Her father reported her missing, and she was found dead the next morning at 6:30 a.m. She was found a short distance from the library, between two abandoned houses slated to be demolished for campus renovations. She had been brutally beaten and stabbed to death. The wires in her Volkswagen's distributor cap had been pulled out. A man's Timex watch with a torn wristband was found nearby. The watch had stopped at 12:24, but police believe that the attack had occurred much earlier.

One month later, on November 29, nearly identical typewritten letters were mailed to the Riverside police and the Riverside Press-Enterprise, titled "The Confession". The author claimed responsibility for the Bates murder, providing details of the crime that were not released to the public. The author warned that Bates "is not the first and she will not be the last".

In December 1966, a poem was discovered carved into the bottom side of a desktop in the RCC library. Titled "Sick of living/unwilling to die", the poem's language and handwriting resembled that of the Zodiac's letters. It was signed with what were assumed to be a set of lower case initials (r h) inscribed below. During the 1970 investigation, Sherwood Morrill, California's top "questioned documents" examiner, expressed his opinion that the poem was written by the Zodiac.

On April 30, 1967, exactly six months after the Bates murder, her father, the Press-Enterprise, and the Riverside police all received nearly identical letters. In handwritten scrawl, the Press-Enterprise and police copies read, "Bates had to die there will be more" with a small scribble at the bottom that resembled either a "2" or a "Z". Bates' father's copy read, "She had to die there will be more", this time without the Z signature. In August 2021, the Riverside Police Department's cold case unit announced that the author of the handwritten letters anonymously contacted investigators in 2016 and was identified via DNA analysis in 2020. He admitted the correspondence was a distasteful hoax and apologized, explaining that he had been a troubled teenager and wrote the letters as a means of seeking attention. Investigators confirmed that the author was not the Zodiac.

On March 13, 1971, five months after Avery's article linking the Zodiac to the Bates murder, the Zodiac mailed a letter to the Los Angeles Times. In the letter, he credited the police, instead of Avery, for discovering his "Riverside activity, but they are only finding the easy ones, there are a hell of a lot more down there". The connection between Bates and the Zodiac remains uncertain. Avery and the Riverside police maintain that the Bates homicide was not committed by the Zodiac but did concede that some of the Bates letters may have been his work to claim credit falsely. In 2016, the Press-Enterprise reported that Riverside police knew who killed Bates but never had enough evidence to arrest them.

Enedine Molina Martinez and Fermin Rodriguez
On June 8, 1967, Enedine Molina Martinez, aged 35, and Fermin Rodriguez, aged 36, were attacked and murdered on Vallecitos Road in Alameda County while relaxing in their vehicle. A stranger approached the couple and told them to get out of the car. Rodriguez was shot dead as he exited the car and the killer abducted Martinez. The killer then stopped by the entrance of Sunol Regional Wilderness, where Martinez was killed trying to escape. Shortly afterward, a nearby resident called the Santa Rita police substation to report two gunshots, resulting in the discovery of the bodies. Rape and robbery were ruled out as motives. The murders occurred close to Pleasanton, where the Zodiac mailed a letter to the Los Angeles Times in March 1971.

John Franklin Hood and Sandra Garcia
On February 21, 1970, 24-year-old Vietnam War veteran John Franklin Hood and his fiancée, 20-year-old Sandra Garcia, visited East Beach in Santa Barbara. The couple were discovered the following day lying face down on their blanket. Hood suffered eleven knife wounds, the majority inflicted to his face and back, while Garcia received the brunt of the vicious attack, leaving her almost unrecognizable. The bone-handled 4" fish knife used in their murder was retrieved from beneath the blanket, partially buried in the sand. There appeared to be no sexual interference and robbery was ruled out. The double-murder bore many similarities to the previous murders of Domingos and Edwards, thirty miles west of the attack and seven years earlier, as well as the Lake Berryessa attack on Hartnell and Shepard.

Kathleen Johns
On the night of March 22, 1970, Kathleen Johns was driving from San Bernardino to Petaluma to visit her mother. Johns was seven months pregnant and was accompanied by her ten-month-old daughter. She first left San Bernardino at 4:30 p.m. While she was driving on Highway 132 west of Modesto, at 11:30 p.m., a man driving behind her blinked his vehicle's lights. Most sources say that both cars pulled over, and the man said her left rear wheel was loose, offering to tighten the lug nuts on it. When he worked on the wheel, he actually loosened the lug nuts, so when Johns drove away, the wheel fell off. The man then offered to drive her and her daughter in his car to a nearby gas station. However, the San Francisco Examiner wrote that when the man stopped Johns, they checked the wheel to find it only had one lug nut, and then he offered a ride.

Once Johns and her daughter were being driven by the man, he drove around for two hours without stopping. Most accounts say that the man threatened to kill Johns and her daughter while driving them around. SFGate writes that at one point, she asked him if always helped out strangers that way, and he said, "'By the time I get through with them, they won't need my help." Johns escaped by jumping out of one the car doors with her daughter. One account says that the man did not stop, and instead continued driving, while Johns' account to Chronicle reporter Paul Avery says that he left the car and searched for her in the dark with a flashlight. A farmer driving by saw Johns, and took her to a nearby police station in Patterson, where she identified the kidnapper as the Zodiac using a sketch that was on a wanted poster there. An hour later, Johns' car was found on Highway 132, intentionally set on fire. The Zodiac took credit for the abduction.

Richard Radetich
On June 19, 1970, around 5:25 a.m., 25-year-old police sergeant Richard Phillip "Rich" Radetich was gunned down by three shots from a .38 caliber revolver through the driver side window of his squad car, while in the process of serving a parking ticket on the 600 block of Waller Street in the Haight Ashbury district of San Francisco. He died around 15 hours later. After Radetich's death, the SFPD started assigning two officers to every patrol car. Police investigated a possible link to the Zodiac, who alluded to the crime in taunting notes to authorities; however, no direct evidence has ever been established between him and Radetich's death. In 2004, the SFPD reopened the Radetich investigation.

Disappearance


Donna Lass worked as a registered nurse at the first aid station of the Sahara Tahoe hotel and casino in Stateline, Nevada. On September 6, 1970, she worked until about 2:00 a.m., treating her last patient at 1:40 a.m. Her last logbook entry was timed at 1:50 a.m. Later that day, both Lass' employer and her landlord received phone calls from an unknown male falsely claiming that Lass had left town because of a family emergency. Lass did not have a family emergency at the time. Lass was never found and the caller has never been identified. Her car was found parked near her apartment, but nobody saw her leave the casino. At her apartment, there were no signs of a struggle, the light was left on, and clothes were left folded.

Suspicious cards
On March 22, 1971, a postcard to the Chronicle, addressed to "Paul Averly" [sic] (Paul Avery) and believed to be from the Zodiac, appeared to claim responsibility for the disappearance of Lass. It has been nicknamed the "Peek Through the Pines card". Made from a collage of advertisements and magazine lettering, it featured a scene of the Lake Tahoe area from an advertisement for Forest Pines condominiums and the text "Sierra Club", "Sought Victim 12", "peek through the pines", "pass Lake Tahoe areas", and "around in the snow". The Zodiac's crossed-circle symbol was in both the place of the usual return address and the lower-right section of the front face of the postcard.

On December 27, 1974, a Christmas card was mailed to Mary Pilker, Lass' sister, portraying trees covered in snow. Once opened it revealed a message that was part of the card itself – "Holiday Greetings and Best Wishes for a Happy New Year", followed by the handwriting "Best Wishes, St. Donna & Guardian of the Pines". The envelope was addressed to "Mrs. Mary Pilker, 1609 South Grange, Sioux Falls, South Dakota". It was postmarked 940, either from San Mateo or Santa Clara County.

Investigation and evidence
Two police reports filed on March 25, 1970, contain possible connections between the Lake Tahoe area and the Zodiac. In the reports, a woman claimed that at a restaurant in South Lake Tahoe, a man wanted to read her astrological chart. Later that day, he came to her house to read an astrological chart that he had prepared. The man was "30- to 40-years-old, 5 foot 9 inches tall, 160 pounds, had a pudgy stomach and wore horn-rimmed glasses", which is similar to the Zodiac's description. He eventually left her house without incident.

In 1986, the Placer County Sheriff's Office located a skull near Emigrant Gap along California State Route 20 in the Sierra Nevada, 70 miles from South Lake Tahoe. In 2023, DNA profiling identified the skull as belonging to Lass. Police said no other evidence was found with the skull, and did not indicate how Lass died or whether homicide was suspected. Investigators at the South Lake Tahoe police department started investigating if there was a connection between Lass' disappearance and the Zodiac in 2001, and have not found one as of 2024.

In 2007, an amateur sleuth claimed to have found the location of the "Peek Through the Pines" card in South Lake Tahoe, and notified police of the area; the police dug two holes in the ground in hopes of finding Lass' body, but they were unsuccessful. In 2021, a rock formation with a shape resembling the Zodiac's bullseye symbol was found in the Sierra Nevada's Hell Hole Reservoir; sources close to the law enforcement investigation into the Zodiac said the formation "doesn’t appear to be a case-breaking development".

Sandy Betts
Sandy Betts is an amateur Zodiac researcher who claims that the people responsible for the Zodiac attacks repeatedly harassed and attacked her. She states that three men were the primary culprits, and that at least one of these core members is identified and still lives in the San Francisco Bay Area. She claimed that one of the culprits has attempted to shoot her multiple times over the years, the most recent attempt in 2009. In 2018, on the 50th anniversary of the Lake Herman Road murders, a group of 30 Zodiac enthusiasts, including Betts, planned to commemorate the murders at the Lake Herman Road site. However, the event was cancelled because a local man threatened to murder the group if they showed up. Betts said this man had stalked her in the past, that he believes his father who tried to kill him was the Zodiac, and that his father went to prison for the attempted murder.

Astrological murders
The "Astrological Murders" were committed by a suspected serial killer who was also active in the same state and around the same time as the Zodiac. Police in Northern California made a tentative connection between a single culprit and possibly at least a dozen unsolved homicides that occurred between the late 1960s and early 1970s. All of the victims were female and were killed in a variety of ways, including strangulation, drowning, throat-cutting, and bludgeoning, occasionally after being drugged. They were linked by the fact that they were dumped in ravines and killed in conjunction with astrological events, such as the winter solstice, equinox, and Friday the 13th. The alleged victims are:
 * Elaine Louise Davis, aged 17, who disappeared on December 1, 1969, from her home in Walnut Creek, California. On December 19, the body of a young woman – eventually identified as Davis after an exhumation in 2000 – was discovered floating off Light House Point near Santa Cruz.
 * Leona LaRell Roberts, aged 16, whose nude body was found ten days before the winter solstice on the beach at Bolinas Lagoon in Marin County, on December 28, 1969. She had been kidnapped from her boyfriend's home on December 10. Her death was treated as a homicide, although the official cause was listed as "exposure" by the medical examiner.
 * Cosette Ann Ellison, aged 15, whose nude body was found in a ravine seventeen days before the vernal equinox. The cause of her death was undetermined. She had been abducted on March 3, 1970, from her residence in Moraga, California, as she got off the school bus at 3:20 p.m.
 * Patricia Ann King, aged 20, was found strangled and discarded in a rural gully at Diablo Valley College. She was nude from the waist down but had not been raped.
 * Judith Ann Hakari, aged 23, was last seen leaving work at Sutter Medical Center in Sacramento at 11:30 p.m. on March 7, 1970, thirteen days before the equinox. She was discovered, nude and bludgeoned, in an overgrown ravine off Ponderosa Way, near Weimar on April 26.
 * Marie Antoinette Anstey, aged 23, who was kidnapped in Vallejo after being stunned by a blow to the head, and then drowned. Her body was recovered in rural Lake County on March 21, and an autopsy revealed traces of mescaline in her bloodstream.
 * Eva Lucienne Blau, aged 17, was found clubbed to death and dumped in a roadside gully near Santa Rosa during the equinox on March 20, 1970. The medical examiner discovered drugs in her circulatory system. She was last seen on March 12, leaving Jack London Hall after telling friends that she was heading home.
 * Carol Beth Hilburn, aged 22, was found beaten to death in a ravine on November 13, 1970. She was last seen at Lloyd Hickey’s Forty Grand Club in Sacramento on November 14 at approximately 5:00 a.m. Hilburn had been stripped of her clothing except for her underwear, which was found around her knees. She had been beaten about the face, and had a deep cut to her throat.
 * Denise Kathleen Anderson, aged 22, who disappeared on April 13, 1971, having been last seen by one of her roommates at 5:30 a.m. at their residence in Sacramento. She has not been seen since.
 * Susan Marie Lynch, aged 22, was discovered murdered on July 31, 1971, having been buried alive near East Levee Road in Sacramento, one-half mile north of Del Paso Road and 0.6 miles southwest of the Hilburn dump site.
 * Linda Diane Uhlig, aged 19, was found in a ditch alongside a rural road beaten to death at Half Moon Bay on March 28, 1972, six days after the vernal equinox. Her skull had been smashed and it appeared that her attacker had tried to decapitate her.
 * Lynn Derrick, aged 24, was discovered in Noe Valley, San Francisco, on July 26, 1972, at 4:15 a.m. She had been strangled and a sock had been forced into her mouth, but no sexual molestation had taken place. Derrick had been abducted from her home approximately two hours earlier, at around 2:00 a.m., when a female neighbour reported hearing a disturbance, a dragging sound, and a car speeding away.

Santa Rosa hitchhiker murders
The Zodiac was also suspected of being the perpetrator behind the so-called "Santa Rosa hitchhiker murders", in which at least seven female hitchhikers were all murdered in Sonoma County and Santa Rosa between 1972 and 1973. The suspicion was based upon similarities between an unknown symbol on his January 29, 1974, "Exorcist letter" to the Chronicle, in which he claims thirty-seven victims, and the Chinese characters on the missing soy barrel carried by victim Kim Allen, as well as stating an intention to vary his modus operandi in an earlier letter to the Chronicle: "I shall no longer announce to anyone. when I comitt my murders, they shall look like routine robberies, killings of anger, + a few fake accidents, etc." (sic)

In addition, Zodiac suspect Arthur Leigh Allen, an elementary school teacher, was independently suspected of being the Santa Rosa killer. He owned a mobile home in Santa Rosa at the time of the murders, had been fired from his Valley Springs teaching position for suspected child molestation in 1968, and was a full-time student at Sonoma State University. Allen was arrested on September 27, 1974, by the Sonoma County Sheriff's Office and charged with child molestation in an unrelated case involving a young boy. He pleaded guilty on March 14, 1975, and was imprisoned at Atascadero State Hospital until late 1977. Graysmith, in his book Zodiac Unmasked, claims that a Sonoma County sheriff revealed that chipmunk hairs were found on all of the Santa Rosa victims and that Allen had been collecting and studying the same species.

April 1970 letter and card
Zodiac continued to communicate with authorities for the remainder of 1970 via letters and greeting cards to the press. In a letter postmarked April 20, 1970, he wrote, "My name is _____," followed by a 13-character cipher that has not been solved to this day. He also said he was not responsible for the recent bombing of the SFPD's police station in Golden Gate Park, which killed Sgt. Brian McDonnell, but added "there is more glory to killing a cop than a cid [sic] because a cop can shoot back." The letter included a diagram of a bomb the Zodiac claimed that he would use to blow up a school bus. At the bottom of the diagram, he wrote: " = 10, SFPD = 0."

On a greeting card to the Chronicle postmarked April 28, 1970, the Zodiac wrote, "I hope you enjoy yourselves when I have my BLAST," followed by the killer's cross-circle signature. On the back of the card, the Zodiac threatened to use the bus bomb soon unless the newspaper published the full details that he had written. He also wanted to start seeing people wearing "some nice Zodiac butons [sic]".

June 1970 letter and map
In a letter postmarked June 26, 1970, the Zodiac stated that he was upset that he did not see people wearing Zodiac buttons, writing, "I shot a man sitting in a parked car with a .38." The Zodiac was possibly referring to the murder of SFPD Sergeant Richard Radetich, who was killed one week earlier after being shot through the window of his squad car by an unidentified gunman during a routine traffic stop. The SFPD denies that the Zodiac was involved in Radetich's death; the murder remains unsolved. Included with the letter was a Phillips 66 roadmap of the San Francisco Bay Area. On the image of Mount Diablo, the Zodiac had drawn a crossed circle similar to those from previous correspondence. At the top of the crossed circle, he placed a zero, a three, six, and a nine. The accompanying instructions stated that the zero was "to be set to Mag. N." The letter also included a 32-letter cipher that the killer claimed would, in conjunction with the code, lead to the location of a bomb that he had buried and set to detonate in the fall. The cipher was never decoded, and the alleged bomb was never located.

July 1970 letters
In a letter postmarked July 24, 1970, the Zodiac took credit for the Kathleen Johns abduction, four months after the incident. In a July 26, 1970, letter, the Zodiac paraphrased a song from The Mikado, adding his own lyrics about making a "little list" of the ways in which he planned to torture his "slaves" in "paradice [sic]". The letter was signed with a large, exaggerated crossed-circle symbol and a new score: " = 13, SFPD = 0". A final note at the bottom of the letter stated, "P.S. The Mt. Diablo code concerns Radians + # inches along the radians." In 1981, a close examination of the radian hint by Zodiac researcher Gareth Penn led to the discovery that a radian angle, when placed over the map per Zodiac's instructions, pointed to the locations of two Zodiac attacks.

October 1970 cards
On October 7, 1970, the Chronicle received a three-by-five-inch (7.6 cm by 12.7 cm) card (nicknamed the "13 Hole Punch Card" ) signed by the Zodiac with the symbol and a small cross reportedly drawn with blood. The card's message was formed by pasting words and letters from an edition of the Chronicle, and thirteen holes were punched across the card. Inspectors Armstrong and Toschi agreed that it was "highly probable" that the card had been sent by the Zodiac.

On October 27, 1970, Avery received a Halloween card (nicknamed as such ) signed with a letter Z and the Zodiac's crossed-circle symbol. Handwritten inside the card was the note, "Peek-a-boo, you are doomed." The threat was taken seriously and was the subject of a front-page story in the Chronicle. The phrase "4-teen" in the letter was interpreted as a possible reference to a 14th victim. Avery started packing a pistol, while Chronicle reporters jokingly started wearing buttons saying "I Am Not Avery". Soon after receiving the letter, Avery received an anonymous letter alerting him to the similarities between the Zodiac's activities and the unsolved Bates murder in Riverside.

March 1971 letter
In the March 13, 1971 letter to the Los Angeles Times, the Zodiac criticized that the police were unable to catch him, saying he had killed 17 victims. Zodiac expert Tom Voigt theorizes that the reason why the letter was postmarked from Pleasanton instead of San Francisco was for the joke of having an unpleasant letter come from "Pleasanton".

Final Zodiac letter
After the Lake Tahoe card, the Zodiac remained silent for nearly three years. The Chronicle then received a letter from the Zodiac, postmarked January 29, 1974, which complained that columnist Count Marco needed to "feel superior to everyone", and praised the film The Exorcist (1973) as "the best saterical comidy [sic] that I have ever seen". The letter included a snippet of verse from The Mikado and an unusual symbol at the bottom that has remained unexplained by researchers. Zodiac concluded the letter with a new score, "Me = 37, SFPD = 0". David Van Nuys, who is also a psychiatrist, believes the reason the Zodiac stopped killing is because he had a case of multiple personality disorder which lessened over time (as with many people who have the disorder), noting that the subsequent Zodiac letters lessened in intensity.

Letters of suspicious authorship
Of further communications sent by the public to members of the news media, some contained similar characteristics of previous Zodiac writings. In 1973, the Albany Times Union in New York received a letter postmarked for August 1. The Zodiac symbol was placed in lieu of a return address. In it, the writer proclaimed they were not "dead or in the hospital", and that they were going to kill again on August 10th. They said that the name and location of their next victim was available in a three-line cryptic code in the letter. FBI cryptanalysts deciphered the code to mean "[REDACTED] Albany Medical Center. This is only the beginning." Investigators could not find the murder that supposedly took place on August 10th, and handwriting experts could not determine if the letter was sent by the Zodiac.

The Chronicle received a letter postmarked February 14, 1974, informing the editor that the initials for the Symbionese Liberation Army, a radical group which had recently kidnapped newspaper heiress Patricia Hearst, spelled out an Old Norse word meaning "kill". However, the handwriting was not authenticated as the Zodiac's.

A letter to the Chronicle, postmarked May 8, 1974, featured a complaint that the movie Badlands (1973) was "murder-glorification" and asked the paper to cut its advertisements. Signed only "A citizen", the handwriting, tone, and surface irony were all similar to earlier Zodiac communications. The Chronicle subsequently received an anonymous letter postmarked July 8, 1974, complaining of their publishing the writings of the antifeminist columnist Marco Spinelli. The letter was signed "the Red Phantom (red with rage)". The Zodiac's authorship of this letter is debated.

In 1976, several letters were sent to a San Francisco newspaper praising David Toschi's investigative work. These letters were eventually discovered to be written by Toschi himself. He was removed from the Zodiac case in 1978, and he later said he regretted writing the letters. Also in 1978, a letter was sent to Chronicle columnist Armistead Maupin that claimed to be from the Zodiac himself. It was alleged the Toschi wrote the letter, which he and the SFPD denied; the SFPD had compared the handwriting of the letter with Toschi's handwriting.

In 2007, an American Greetings Christmas card sent to the Chronicle, postmarked 1990 in Eureka, was re-discovered in the paper's photo files by editorial assistant Daniel King. This letter was handed over to the Vallejo police. Inside the envelope, with the card, was a photocopy of two United States Post Office keys on a magnet keychain. The handwriting on the envelope resembles Zodiac's print but was declared inauthentic by forensic document examiner Lloyd Cunningham; however, not all Zodiac experts agree with Cunningham's analysis. The discovery "electrified" Zodiac researchers; the letter, if it is real, disproves the theory that the Zodiac stopped killing due to his own death or imprisonment, and many theorized he could still have been alive.

21st-century developments
In April 2004, the SFPD marked the case "inactive", citing caseload pressure and resource demands, effectively closing the case. However, they re-opened their case sometime before March 2007. The case is open in Napa County and in the city of Riverside. In May 2018, the Vallejo Police Department announced their intention to attempt to collect the Zodiac's DNA from the back of stamps he used during his correspondence. The analysis, by a private laboratory, was expected to check the DNA against GEDmatch. It was hoped the Zodiac would be caught in a similar fashion to serial killer Joseph James DeAngelo. In May 2018, a Vallejo police detective said that results were expected in several weeks. As of December 2019, no results had been reported. The FBI's investigation was still continuing as of 2020.

Suspects
In 2007, The Guardian wrote that over 2,500 people have been brought up as a possible Zodiac suspect, and at least a half dozen names were credible. The SFPD had investigated an estimated 2,500 suspects by 2009. Richard Grinell, who runs the website Zodiac Cyphers, said in 2022 that "there are probably 50 or 100 suspects named every year".

Background
The only man ever named by the police as a Zodiac suspect is Arthur Leigh Allen, a former elementary school teacher and convicted sex offender, who died in 1992. Allen denied being the culprit. In Zodiac, Graysmith advanced Allen as a potential suspect, based on circumstantial evidence. Allen had been interviewed by police from the early days of the Zodiac investigations and was the subject of several search warrants over a twenty-year period. In 2007, Graysmith noted that several detectives described Allen as the most likely suspect. In 2010, Dave Toschi stated that all the evidence against Allen ultimately "turned out to be negative".

Allen entered the United States Navy in 1951 and served until his honorable discharge in 1959. During his time in the navy, he served mostly in the reserves but spent some time on active duty. He served on multiple submarines and earned the China Service Medal for his service in southeast Asia. In 1958, Allen faced a special court-martial at Treasure Island for bringing a loaded .45 automatic pistol onto the naval base. He was found not guilty.

Allen lived in Vallejo, and worked minutes away from where Zodiac victim Darlene Ferrin lived and from where one of the killings took place. Jack Mulanax of the Vallejo Police Department wrote that Allen had been fired from his teaching job in March 1968 after allegations of sexual misconduct with students. He was generally well-regarded by those who knew him, but he was also described as "fixated on young children and angry at women".

Investigation
On October 6, 1969, Allen was interviewed by Detective John Lynch of the Vallejo Police Department. Allen had been reported in the vicinity of the Lake Berryessa attack on September 27, 1969. He said he was scuba diving at Salt Point that day. Allen again came to police attention in 1971 when his friend Donald Cheney reported to police in Manhattan Beach that Allen had spoken of his desire to kill people, used the name Zodiac, and secured a flashlight to a firearm for visibility at night. According to Cheney, this conversation occurred no later than January 1, 1969. Allen was interviewed by the police again in 1971. In September 1972, the SFPD obtained a search warrant for his residence. In 1974, he was arrested for lewdness with a nine year old boy. After pleading guilty, he was sent to Atascadero State Hospital for pre-sentence evaluation and treatment. On May 13, 1977, Allen was given a suspended prison sentence and five years of felony probation. He completed probation successfully in 1982. Vallejo police served another search warrant at Allen's residence in February 1991. Two days after Allen's death in 1992, Vallejo police served another warrant and seized property from his residence.

Evidence
Dave Toschi's daughter said that her father had always thought Allen had been the killer, but they did not have the evidence to prove it. Mark Ruffalo, who portrayed Toschi in the 2007 film about the Zodiac, commented, "If you get into who these cops were, you realize how they have to take their hunches, their personal beliefs, out of it. Dave Toschi said to me, 'As soon as that guy walked in the door, I knew it was him.' He was sure he had him, but he never had a solid piece of evidence. So he had to keep investigating every other lead." Retired police handwriting expert Lloyd Cunningham, who worked on the Zodiac case for decades, stated, "They gave me banana boxes full of Allen's writing, and none of his writing even came close to the Zodiac. Nor did DNA extracted from the envelopes [on the Zodiac letters] come close to Arthur Leigh Allen."

In July 1992, Michael Mageau identified Allen as the man who shot him in 1969 from a photo line-up, saying "That's him! It's the man who shot me!" However, police officer Donald Fouke, who is speculated to have seen the Zodiac fleeing from the Stine killing, said in the 2007 documentary His Name Was Arthur Leigh Allen that Allen weighed about 100 pounds more than the man he saw, adding that his face was "too round". Nancy Slover, who received the call from the Zodiac in the aftermath of the Mageau/Ferrin shooting, said that Allen did not sound like the man on the phone. A letter sent to the Riverside Police Department from Bates' killer, which was typed with Elite type on a Royal typewriter, the same brand found during the 1991 search of Allen's residence. Allen owned and wore a Zodiac Sea Wolf wristwatch, which used the same logo as the Zodiac Killer in his letters. They both wore shoes sized 10 and a half.

In 2002, the SFPD developed a partial DNA profile from the saliva on stamps and envelopes of Zodiac's letters. The SFPD compared this partial DNA to that of Allen. A DNA comparison was also made with the DNA of Don Cheney, who was Allen's former close friend and the first person to suggest Allen may be the Zodiac. Since neither test result indicated a match, Allen and Cheney were excluded as the contributors of the DNA. His fingerprints also did not match those lifted from the Stine murder.

Earl Van Best Jr.
In 2014, Gary Stewart and Susan Mustafa published a book, The Most Dangerous Animal of All: Searching for My Father... and Finding the Zodiac Killer, in which Stewart claimed his search for his biological father, Earl Van Best Jr., led him to conclude Van Best was the Zodiac. Stewart based his theory on circumstantial evidence, including a police sketch resembling Van Best, partial fingerprint and handwriting matches, encrypted messages in Zodiac letters, and partial DNA connections.

In 2020, the book was adapted for FX Network as a documentary series. To validate Stewart's claims, the producers enlisted private investigator Zach Fechheimer, who uncovered that Stewart had manipulated a police report and traced Van Best Jr.'s presence in Europe during the Zodiac's activities. Additionally, experts discredited the DNA analysis and the handwriting and fingerprint matches. The producers chose to withhold their findings until near the end of the year-long production to minimize their impact on both the series and Stewart. Six months after production, director Kief Davidson stated that he thought Stewart's father was not the Zodiac, while executive producer Ross Dinerstein remained uncertain about Van Best Jr.'s potential involvement.

Gary Francis Poste
In 2021, the Case Breakers, an independent group made up of around 40 "former law enforcement officials, academics, journalists, and former military intelligence workers", said they had identified a man who died in 2018, Gary Francis Poste, as the Zodiac Killer, also stating he murdered Cheri Jo Bates.

The FBI stated that the case remained open and that there was "no new information to report". Local law enforcement expressed skepticism regarding the team's findings. Riverside police officer Ryan Railsback said the Case Breakers' claims largely relied on circumstantial evidence. Rumors about Poste as a suspect had been investigated by the SFPD in 2017. They visited his jail, but declined to say if they interviewed him. In 2023, the Case Breakers claimed an FBI whistleblower told them the bureau had considered Poste a suspect since 2016.

Poste was an Air Force veteran. He had a history of violence; he pushed his wife into a wall, breaking her pelvis, and his relative claimed Poste tried to attack him with a hammer. Poste allegedly had a group of young male followers who he trained to be "killing machines", and who often attacked animals.

One piece of evidence used by the Case Breakers involved forehead scars that were supposedly present on both Poste and the Zodiac. Tom Voigt called the claims "bullshit", noting that no witnesses in the case described the Zodiac as having forehead scars. They also say that the Zodiac and Poste had the same shoe size, and claim that DNA from the Bates murder will match Poste's.

Poste had been investigated as a suspect in the case since at least 2014, by TV news anchor Dale Julin. Julin filed affidavits in court that said he interviewed Poste in 2017, and Poste admitted to being the Zodiac. The Union Democrat found the information in the affidavits to be unverifiable. Julin also claimed he used supposed anagrams found in the Zodiac's letters (the 13 Hole Punch Card, Halloween Card, and the Peek Through the Pines card) to find the tree where Poste, as the Zodiac, hanged Donna Lass. Julin's solve for the codes contained Poste's name and gave the coordinates of a specific pine tree in a section of Zephyr Cove RV Park and Campground near U.S. Highway 50. The tree in question had been gouged at the base. The Case Breakers partially based their research on Julin's book on the subject, Catching Zodiac, which was released in 2024.

Giuseppe Bevilacqua
In 2017, Italian journalist Francesco Amicone conducted an investigation that implicated Joseph “Giuseppe” Bevilacqua, a retired Army sergeant and former superintendent of the Florence American Cemetery and Memorial, as a suspect in both the Zodiac and Monster of Florence (Il Mostro) cases. Bevilacqua testified at the trial of Il Mostro suspect Pietro Pacciani in 1994. Starting in May 2017, Bevilacqua and Amicone began having multiple meetings, and according to Amicone, during a phone call in September, Bevilacqua implied his responsibility for both cases. He agreed with Amicone's request to turn himself in, but later changed his mind. The conversation was not recorded. Amicone's inquiry was published in multiple Italian magazines  and has been continued since then on his blog. Italian authorities dismissed their investigation into Bevilacqua in 2021. Bevilacqua died on December 23, 2022. Amicone claimed a DNA profile was sent to the US authorities investigating the Zodiac case in November 2023.

Lawrence Kane
In a photo lineup, Kathleen Johns identified Lawrence Kane (also known as Lawrence Kaye) as her abductor. Darlene Ferrin's sister Linda identified a photo of Kane as showing the man who once harassed Darlene in a restaurant. Patrol officer Don Fouke, who possibly observed the Zodiac following the Stine shooting, said that Kane resembled the man he and Eric Zelms had observed more than any other person.

Kane worked at the same Nevada hotel as Donna Lass. He was arrested for voyeurism in 1961 and prowling in 1968. He was diagnosed with impulse-control disorder after suffering brain injuries in a 1962 accident. He died in 2010. Fayçal Ziraoui, a French-Moroccan business consultant, claimed in 2021 that he solved the Z13 cipher and the solution to the puzzle reads, "My name is Kayr", which he said is a likely typo for Kaye. Others disputed that Ziraoui could have solved the cipher.

Paul Doerr
In 2022, author Jarrett Kobek published How to Find Zodiac, in which he named Paul Doerr as a suspect. Doerr was a North Bay resident with a post office box in Vallejo, where the first murders took place. Born in 1927, Doerr's age in 1969 (42) as well as his height (5'9") was consistent with witness estimates. He was an avid fanzine publisher and letter-writer throughout the 1960s and 1970s, and many of his writings exhibit circumstantial parallels with the Zodiac. Paul Haynes, a researcher for I'll Be Gone in the Dark, called Doerr "the best Zodiac suspect that's ever surfaced". Doerr's daughter read Kobek's book with the intent of suing for libel, but came away impressed with his research, adding in interviews that Doerr had at times been a violent and abusive father. Kobek sent a 19-page document to the SFPD's Major Crimes Division regarding the similarities, which he did not receive a response to.

Doerr was a member of the Minutemen, a right-wing militant group which sent out threatening letters to supposed Communists using a symbol which resembled the Zodiac's. Some of the Zodiac attacks also took place at hangouts spots of Doerr's daughter. In his fanzine Pioneer, Doerr references the same formula for an ANFO bomb given later by the Zodiac, which Kobek argues was not widely known before the Internet and the publication of The Anarchist Cookbook in 1971. Doerr hinted in a 1974 letter to the journal Green Egg that he had previously killed people. Kobek said that part of his message was not intended for publication, but Green Egg had a policy of publishing every letter in full.

Doerr was interested in cryptography; in issue #1 of his Tolkien fanzine Hobbitalia, he published a cipher in Cirth. This came three days after Zodiac sent the Z13 cipher, and Kobek argues that the solution to the Hobbitalia cipher is one of only three possible solutions to Z13. In Hobbitalia #2, Doerr praised the Society for Creative Anachronism, a group of medieval cosplayers, which could explain the "executioner's hood" used at Lake Berryessa. A Renaissance Faire also took place locally the day of the attack, and there is an undated photo which shows him carrying a knife similar to the one described at the lake. Doerr also made a list of books he wanted to sell, including The Strange Ways of Man, which describes headhunters killing victims so they could have slaves in the afterlife. In a letter to a different fanzine in 1970, Doerr advocated using solely 1¢ stamps to spite the Post Office, a practice the Zodiac employed on some of his letters.

Richard Gaikowski
At the time of the murders, Richard Gaikowski was a reporter and editor who worked for Good Times and the Martinez Morning News Gazette. He moved to the Bay Area in 1963. In 1971, he was involuntarily committed to Napa State Mental Hospital and diagnosed with a mental illness. He later operated a movie theater, and died in 2004. He is Tom Voigt's top suspect.

His appearance resembled the Stine composite sketch, and the word "Gyke" also appears in the Zodiac cypher that claimed to contain his identity. When he was working for the Gazette, he was minutes away from two Zodiac murder scenes. Paul Stine's sister told Voigt she recognized Gaikowski at Stine's funeral. This would also match with the claim that Ferrin's attacker and boyfriend were named Richard.

When Ken Narlow interviewed Gaikowski, he said he was not in the United States at the time of the Lake Herman Road murders, but he lost his passport. According to Voigt, the FBI investigated Gaikowski, but dismissed him upon hearing the claim he was out of the country. This is despite him losing his passport. San Francisco and Napa police have declined to compare DNA samples of Gaikowski and the Zodiac.

A former coworker of Gaikowski, nicknamed "Goldwatcher", wrote long letters to law enforcement accusing him of being the Zodiac. In 2009, an episode of the History Channel television series MysteryQuest investigated Gaikowski, and Goldwatcher made an appearance in disguise. On the episode, he provided recordings of Gaikowski's voice. Nancy Slover, the Vallejo police dispatcher who was contacted by the Zodiac shortly after the Blue Rock Springs attack, identified a recording of Gaikowski's voice as being the same as the Zodiac's. However, History referred to Goldwatcher as a "conspiracy theorist with low credibility", and a San Francisco police dispatcher referred to him as "one of the top three Zodiac kooks".

Richard Marshall
Richard Marshall was a ham radio operator and movie projectionist. Marshall lived in Riverside in 1966, and later in San Francisco, close to the scene of the Stine murder. Visitors to his home found him "peculiar", and he often mentioned finding "something much more exciting than sex". Marshall liked the movie The Red Phantom, which is the phrase a possible Zodiac letter used. He lived in a basement apartment, which the Zodiac mentioned. Like the Zodiac, he owned felt-tip pens and "odd-sized" paper, and the two used a similar typewriter and teletype. In 1989, Marshall acknowledged that similarities existed, but denied being the Zodiac. Ken Narlow said that "Marshall makes good reading but [is] not a very good suspect in my estimation." Marshall died in 2008.

Ross Sullivan
Ross Sullivan became a person of interest through the possible link between the Zodiac and the Bates murder. Sullivan was a library assistant at Riverside City College and was suspected by coworkers after he made them uncomfortable and went missing for several days following the murder. Sullivan resembled sketches of the Zodiac, as he sported a crew cut, and wore glasses and military-style boots with footprints like those found at the Lake Berryessa crime scene. Sullivan moved to Northern California in 1967, and was hospitalized multiple times for bipolar disorder and schizophrenia.

Highly-criticized suspects

 * Serial killer Edward Edwards, who committed five murders between 1977 and 1996, was linked to the Zodiac murders and several other unsolved cases by former cold case detective John A. Cameron. Cameron's theories were met with "almost universal disdain, especially from law enforcement".
 * Dennis Kaufman claimed that his stepfather, Jack Tarrance, was the Zodiac. Kaufman claimed he resembled the Zodiac, and claimed to have multiple items of incriminating evidence, including a roll of film depicting possible victims and a hooded costume like the Zodiac's costume at Lake Berryessa. In a 2007 documentary on the Discovery Channel, a document examiner said Tarrance's handwriting matched the Zodiac's. However, law enforcement dismissed Kaufman's evidence as "nonsense". He claimed one photo, which looked like a "blob of color", was actually the Black Dahlia, and Tarrance's costume was considered "cruder" than the Zodiac's at Lake Berryessa. The document examiner's credibility was challenged by researchers; one reason was that she claimed that Tarrance had also written the ransom note in the JonBenet Ramsey case.

Cleared suspects

 * Following the capture of Charles Manson and his murderous cult, the Manson Family, a 1970 report by the California Bureau of Criminal Identification and Investigation stated that all male members of the Manson Family had been investigated and eliminated as Zodiac suspects. There have been attempts to link the two Santa Barbara County shootings with the Manson Family due to their ties to the city of Santa Barbara, but there has so far been no evidence of a connection.
 * According to Tom Voigt, fingerprint comparison in 1989 eliminated serial killer Ted Bundy as a person of interest.
 * Ted Kaczynski, a domestic terrorist and mathematician also known as the Unabomber, was investigated for possible connections to the Zodiac in 1996. Kaczynski worked in northern California at the time of the murders and, like the Zodiac, had an interest in cryptography and threatened the press into publishing his communications. Kaczynski was ruled out by both the FBI and SFPD based on fingerprint and handwriting comparisons, and by his absence from California on certain dates of known Zodiac activity.

Legacy
The Chronicle wrote that the Zodiac case is "arguably the most famous unsolved murder case in American history". The unusual nature of the case led to international interest that has been sustained throughout the years. It is the subject of many investigations by amateur sleuths, and is covered in multiple books — more than 50 by 2022 — and documentaries. Multiple websites are devoted to cracking the Zodiac's ciphers. People who research him are known as "Zodiologists". As of 2018, an investigative "task force" meeting of Zodiologists is held annually in the Bay Area, which has been ongoing since 2002; this is the same meeting which was cancelled in 2018 due to threats of violence.

The Zodiac inspired the nickname of Heriberto Seda, who, in the 1990s, committed three murders in New York City as "the Zodiac". The 1997 Kobe child murders in Japan were also inspired by the Zodiac. In 2021, threatening letters were sent to media outlets in New York by a person named the "Chinese Zodiac Killer".

The Zodiac inspired characters in numerous movies, including Dirty Harry, The Exorcist III, Seven, and The Batman. In 2007, the movie Zodiac was released. It was directed by David Fincher as an adaptation of Graysmith's books. It focuses on Avery and Graysmith's reporting and investigation over a period of 23 years. The acclaimed film was extensively researched, and the filmmakers conducted interviews with people involved with the case. However, Zodiac researchers said the film had inaccuracies, such as a scene featuring Darlene Ferrin's sister which never happened. The film, which believes in Arthur Leigh Allen's culpability, led to more public interest in the case.

Literature

 * Ronald J. Dayton (2018), Zodiac 340 Cipher, Inner Rapport Publishing ISBN 978-0-244-43599-8
 * Michael H. Stone, M.D. & Gary Brucato, Ph.D., The New Evil: Understanding the Emergence of Modern Violent Crime. Amherst, NY: Prometheus Books, pp. 113–128. ISBN 978-1-63388-532-5
 * Ronald J. Dayton (2018), Zodiac 340 Cipher, Inner Rapport Publishing ISBN 978-0-244-43599-8
 * Michael H. Stone, M.D. & Gary Brucato, Ph.D., The New Evil: Understanding the Emergence of Modern Violent Crime. Amherst, NY: Prometheus Books, pp. 113–128. ISBN 978-1-63388-532-5
 * Ronald J. Dayton (2018), Zodiac 340 Cipher, Inner Rapport Publishing ISBN 978-0-244-43599-8
 * Michael H. Stone, M.D. & Gary Brucato, Ph.D., The New Evil: Understanding the Emergence of Modern Violent Crime. Amherst, NY: Prometheus Books, pp. 113–128. ISBN 978-1-63388-532-5

FBI files

 * FBI Case File (1 of 5) on the Zodiac Killer. 89 pages.
 * FBI Case File (2 of 5) on the Zodiac Killer. 109 pages.
 * FBI Case File (3 of 5) on the Zodiac Killer. 258 pages.
 * FBI Case File (4 of 5) on the Zodiac Killer. 208 pages.
 * FBI Case File (5 of 5) on the Zodiac Killer. 373 pages.