AUDIE CORNISH, HOST:
Local police now have access to a firearms forensic tool that is managed by the Bureau of Alcohol, Tobacco, Firearms and Explosives. But defense attorneys are pushing back against evidence they say is not scientific. Oregon Public Broadcasting's Jonathan Levinson reports.
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JONATHAN LEVINSON, BYLINE: Portland Police Officer Jason Hubert is test firing a handgun at the department's North Precinct. Officers recently took it from a suspect.
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LEVINSON: He then places the casings under a microscope. He's about to enter the shell casing into the National Integrated Ballistics Information Network, or NIBIN, a nationwide database of high-resolution images of shell casings started by the ATF in 1999. Hubert fires two rounds into a large trap filled with a thick sludge.
JASON HUBERT: I'm looking for a good ejector mark.
LEVINSON: That's the mark left on the casing as it's expelled from the gun. He'll pick one to go into NIBIN.
HUBERT: And the ejector mark is basically the fingerprint of the shell casing.
LEVINSON: At the Portland police department, this is all new. Until last July, these casings had to be sent to a crime lab. Results would take months to get back, and they were only used by firearms examiners to testify at trial.
SUZANNE HAYDEN: That's of no help in investigators' use of that technology to try to figure out who shot the gun.
LEVINSON: Assistant U.S. Attorney for the District of Oregon Suzanne Hayden helped get the NIBIN system into police departments so they could be used in local investigations.
HAYDEN: Each firearm that shoots a bullet leaves an imprint that's unique to that firearm.
LEVINSON: So the idea is - find a casing that matches in NIBIN, and police may be able to connect multiple shootings and make arrests before the gun is used again. But the argument that the imprint is unique, that's a sticking point. Janis Puracal is an attorney and the founder of the Oregon-based Forensics Justice Project.
JANIS PURACAL: The problem is that no one's gone out and actually determined that it could only be matched to that gun to the exclusion of all other guns in the universe.
LEVINSON: Flawed firearms forensics have led to exonerations. In 2013, a Mississippi man's life was spared hours before his scheduled execution after the FBI said experts had overstated the science. In a letter to the district attorney in that case, the bureau said examiners may only testify to a reasonable degree of scientific certainty. Department of Justice guidelines say examiners may only offer an expert opinion. But the opinions that form during an investigation, Puracal says they can be problematic, too.
PURACAL: It's the idea that once we start building that narrative and it starts making sense, the more things that we see that fit into that same narrative.
LEVINSON: Almost 200 agencies own NIBIN terminals and are using the data as an investigative tool.
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UNIDENTIFIED PERSON #1: We got a (unintelligible) regarding the...
LEVINSON: On a recent night in Portland, Sergeant Steven Wilbon has his eye on a car parked down the street from Jefferson High School. He pulls up and talks to the three people inside about the homecoming game that's just getting out.
STEVEN WILBON: Who won?
UNIDENTIFIED PERSON #2: Jefferson...
WILBON: Jefferson.
LEVINSON: He drives off and runs the plates.
WILBON: All right.
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LEVINSON: The computer tells him it's been reported stolen.
WILBON: It's a stolen car.
LEVINSON: Officers approach the car from both sides.
UNIDENTIFIED OFFICER: Do have a valid concealed carry permit?
UNIDENTIFIED PERSON #2: I don't have (unintelligible)...
UNIDENTIFIED OFFICER: Well - I know you're saying it's not your gun. But...
WILBON: Yeah, it's in the back of this car.
LEVINSON: OK.
WILBON: It's in his waistband - or it's in his pocket. He's not denying it. So...
LEVINSON: Wilbon says they found three loaded guns inside - without the permits required in Oregon. And two of the people had outstanding warrants. Because the Portland police have this new equipment, the casings were immediately entered into NIBIN. Seattle Police use it, too. And the ATF database indicated a match to shootings there. A police department spokesperson in Seattle says it was a lead that moved their case forward, which is exactly how the Department of Justice intends for NIBIN to be used.
For NPR News, I'm Jonathan Levinson in Portland.
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CORNISH: That story comes to us from Guns & America, a public media reporting project on the role of guns in American life.
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