User:Nimsten

Summary:
There are many different types of weapons that can be used in crimes. These include revolvers, automatic and semiautomatic weapons, rifles, and even shotguns. Each type of gun has a different build, bullet type, backfire, etc. The type of weapon used in a crime is a big indicator as to who committed the crime, how it was committed, and where it happened.

Revolvers:
The first revolver was invented by Elisha Collier in 1818. The revolver is a gun with revolving cartridges (hence the name). Most revolvers have either 6, 8, or 10 cartridges. A mini-explosion propels the bullet out of it's cartridge, into the barrel, and out at the target. Revolvers have been used in many crimes since their creation. No weapon could be hidden better than the revolver because of its small size, light weight, and slender build. Revolvers, like other more modern handguns have fairly small bullets. "Caliber" is the approximate diameter of a bullet and is the universal method to classifying bullets. Most revolver gun calibers fall between .22-.56.

Automatic and Semiautomatic Weapons:
A semiautomatic weapon is a weapon which sets up the bullet to fire completely on its own without help from the wielder of the weapon. German gunsmith Ferdinand Ritter von Mannlicher is credited with the invention of the semiautomatic rifle in 1885. About four years later American gunsmith John Moses Browning created the first semiautomatic shotgun. Semiautomatic weapons are much bigger than revolvers, have a longer barrel, usually have more firing power, and thus they deliver a stronger backfire. Automatic weapons, unlike all other gun types, immediately load another bullet after one has been fired. This allows for a much higher firing rate. Also attributed with automatic weapons is a very strong backfire, entirely metal structure, and a high firing power. Semiautomatic weapon calibers can be found in a range of .308-.56. Automatic weapon calibers range anywhere between a low .3 to the famous "50 caliber", or .5 caliber heavy machine gun.

Connection to Forensic Chemistry:
Forensic Scientists have used weapons to their advantage in pinning criminals since the invention of the first gun. Guns opened a new window of opportunity for criminals, but they also helped Forensic scientists. Scientists could now determine exactly where the criminal was standing when he fired the weapon, in which direction he was facing, which weapon he was using, and much more.

Blood Spatters:
By the blood spatter created by the bullet, scientists can determine where the criminal was, how far away, and what type of weapon he was using. A revolver and an automatic weapon are going to make very different blood spatter patterns, the first being only a few heavy spots, and the second making many lighter spots. Depending on the size of the radius of the blood spatter, scientists can determine the power of the weapon and the distance from the victim at which it was fired.

By-products of firing a weapon:
Powder always flies out of handguns when they fire, and this condition can be found in rifles and even some shotguns. Also, a small amount of smoke is discharged in older revolvers and rifles. All of these by-products of firing a gun can be used by scientists to determine the type of weapon used in a crime.

Bullet Wound Analysis:
The bullet wound, in a situation where the bullet passed cleanly through the body, is very helpful to forensic scientists. Depending on the way the skin and muscle is torn, the bullet caliber and size can be determined, allowing scientists to peg the type of gun used. If the bullet got lodged in the body and did not escape then it can be retrieved by scientists and a bullet and gun type can quickly be determined.

Background Information:
Forensic Scientists have used guns and bullets as evidence against criminals since the first use of a weapon in a crime. Forensics probably used weapons as early as the early 1800s. Even though they could not determine where the shooter stood, they could find the bullet and determine it's type and the gun it was fired by. This made it much easier to find the perpetrators of a crime.

State v. Tager
A gunman confronted NBC Today Show and shot and killed an employee. The gunman had assaulted CBS newsman Dan Rather in years past and had killed him in this attack. The case was argued on July 9, 1980 and was decided upon (in favor of the state) on October 20, 1980. Forensic Scientists used the murder weapon and the bullets fired to prove that the alleged gunman was indeed the gunman who killed Dan Rather.

References:
Book 1: Wills, Chuck. Weaponry: An Illustrated History. New York City: HYLAS Publishing, 2007. Print. (pages used: 70-83)

Book 2: Saferstein, Richard. Criminalistics: An Introduction to Forensic Science. Volume 8. Saddle River: Stephen Helba, 2004. Print. (pages used: 432-454)

Internet Source 1: (Unknown Author). Firearms Tutorial. Utah Med Students.University of Utah. Department of Forensic Science, 15, April 2012. Web. 

Internet Source 2: Welner, Michael. Pathology: Criminal Law. The Forensic Panel. Expert Services, 15 April 2012. Web. 

Internet Source 3: Court of Appeals. 638 F. 2d 167 - United States v. Tager. Open Jurist. 15 April 2012. Web. 