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Forensic Science Profile

Firearm and toolmark forensic scientist specializes in finding valuable marks on a variety of materials

James Cadigan, a forensic toolmark examiner and group manager at ORAU says he made it about 30 seconds into his first episode of CSI before turning to his wife and saying, “You can’t really do that.”

“The most common misconception about forensics is that it happens quickly,” explains Cadigan. “Some of the examinations we do take days, and you don’t always get positive results—it totally depends on the evidence you are given.”

Cadigan has seen mountains of evidence in a career that included 31 years with the FBI, and investigations into some of America’s darkest events, including the Oklahoma City bombing and the World Trade Center bombing. In all, he’s worked more than 4,500 cases, examining more than 27,000 pieces of evidence.

Cadigan specializes in firearm and toolmark analysis. Toolmark analysis involves comparing scratches, indentations and other marks left at a crime scene with the tools or implements that could have made them. For example, during the Oklahoma City bombing investigation, Cadigan matched a drill bit found in the basement of Terry Nichols’ house to the unique marks made when that drill bit was used to drill out a lock and steal explosives linked to the bombing. Nichols was convicted for his role in that case. Firearms identification deals specifically with comparing unique marks on bullets, cartridge casings and other ammunition components with particular firearms to determine if a particular firearm was used in the commission of a crime.

At ORAU, Cadigan and his team of toolmark specialists are helping to strengthen efforts to keep our citizens safe at home and abroad. For example, by analyzing components from various types of material they can identify unique imprints that may reveal a pattern in multiple attacks, which can help prosecute and convict the perpetrators when they are captured.

Technology has automated some analysis. For example, there is a computer program that makes digital comparisons of marks on cartridge casings. However, this hasn’t replaced painstaking human analysis. Unlike the software for bullet analysis, there is currently no commercially available software to help compare marks on pieces of an explosive.

“I spent days comparing a cast taken from an item of evidence to thousands of examples on file. I didn’t find a match, but now we can add this to a file for later comparisons,” said Cadigan. “I am just glad to be part of the effort to help keep Americans safer, especially those facing danger as they perform their jobs at home and overseas.”

James Cadigan

James Cadigan, senior forensic toolmark examiner at ORAU.