User:Rlrogers/DNA Wars

United States v. Yee et al.
In 1988, David Hartlaub was murdered just before making a deposit at a bank in Sandusky, Ohio. The victim’s body was pushed from his van, and his attackers drove off, abandoning the vehicle at a nearby hotel. The murder weapon was found in the vehicle along with large bloodstains. Initial analyses revealed that while some of the blood belonged to Hartlaub, a portion had also come from another source, most likely Hartlaub’s killer.

There were no eyewitnesses in the case, but based on corroborating evidence, three members of the Cleveland Hell’s Angels were arrested for murder. The prosecution claimed that Wayne Yee, Mark Verdi, and John Ray Bonds had planned a hit on a rival from a neighboring gang. Mistaking Hartlaub’s van for that of their rival, they shot Hartlaub instead. Using DNA fingerprinting, the FBI identified Bonds as a genetic match with blood at the crime scene.

Expert Witnesses Testimony on DNA Fingerprinting
The defense contacted Richard Lewontin and Daniel Hartl, requesting comments on the statistical validity of the forensic DNA testing methods the FBI used. Hartl and Lewontin along with court witness Eric Lander, found grave scientific shortcomings in the analyses performed by the FBI.

Lewontin and Hartl’s criticisms focused largely on the ways in which the FBI’s assumptions about population structure could affect the statistical validity of DNA testing. The FBI claimed that individuals within each racial group mated randomly, leaving the population well mixed. It then used gene frequencies from a database of random individuals to calculate the probability of any given match happening by chance.

Hartl and Lewontin pointed out that individuals within ethnic groups tended to seek partners with similar religion and culture and often remained within their geographic region. This non-random mating could cause gene frequencies to vary among groups, leaving two individuals from the same subgroup more likely to produce DNA match than two individuals from a well-mixed population.

The scientists also cited issues with the interpretations of gel electrophoresis techniques, pointing out that two DNA fragments could appear to be the same size, but might actually carry entirely different sequences. Also, the same sequence might run through the gel at different rates in different replicates, making it difficult to discern the true size of any given fragment.

These issues together meant that the chance of a randomly selected person matching the DNA profile at the crime scene was considerably higher than the FBI claimed. Based on these significant problems, the defense lobbied to prevent the admission of DNA evidence from the trial. The judge however, allowed the trial to continue with the DNA fingerprinting as evidence. All three defendants, Yee, Bonds, and Verdi, were convicted of murder and lost their appeal.

Controversy Surrounding Publication
After the trial, Hartl and Lewontin detailed these objections in a manuscript submitted to the journal Science. The work was accepted, and the proofs of the work sent to Lewontin. Prior to publication of the work, Hartl received a telephone call from James Wooley, who, Hartl claims, attempted to pressure him into withdrawing the work. Hartl refused. Wooley contends that the discussion was entirely amiable and has denied all allegations of inappropriate conduct or attempts to suppress the paper, but claims his intentions were misinterpreted.

Around the same time, C.Thomas Caskey approached Daniel Koshland, the editor at Science. Caskey was a prominent supporter of DNA forensics and had licensed DNA fingerprinting techniques to one of the largest forensic companies. Caskey, as well as FBI and federal prosecutors began to pressure Koshland to halt publication at least until a separate piece could be put together refuting Lewontin and Hartl’s claims.

Upon hearing Caskey’s objections, Koshland requested that Lewontin and Hartl revise their paper to soften the conclusions. He also commissioned a rebuttal by Ranajit Chakraborty, a co-recipient along with Caskey of a $200,000 grant from the Department of Justice to study DNA typing, and Kenneth Kidd, a frequent witness in DNA forensic trials. The rebuttal appeared in the same issue of Science just before Lewontin and Hartl’s piece and was exempt from the typical peer review process.

Debate within the Scientific Community
The publication of Lewontin and Hartl’s manuscript along with the rebuttal sparked a debate within the scientific literature that lasted even after the OJ Simpson trial in 1994. While much of the fracas focused on the scientific issues surrounding the probability of a DNA match, at heart were also two separate issues concerning government intervention in the scientific literature and the standard of proof that should be required for a conviction.