FBI Forensic Experts Claim Mass-Produced Jeans And Shirts Are As Distinct As Fingerprints And DNA

(Mis)Uses of Technology

from the evidentiary-clown-show dept

The evidence the feds use to lock people up continues to be laughable. Well, laughable under any other circumstances. Freedom is a high price to pay for bad science, but the FBI seems to believe the tradeoff between lost freedom and junk science is a net gain for society. Judges seem to agree. It’s difficult to challenge the sufficiency of evidence against you, nevermind the underlying “science” backing dubious forensic evidence like hair or bite mark matching.

The gold standards in forensic evidence aren’t even gold. DNA is a hitchhiker which can put people never involved with a crime at the scene just by hitching a ride on first responders. Fingerprints have been considered individual markers for years, but even that assessment appears to have been overstated.

But dig deep enough into the FBI’s forensic toolkit and you’ll find some truly surprising forms of “evidence.” ProPublica has done exactly that, uncovering so-called science that far more resembles faith. Convictions have been obtained thanks to FBI forensic experts claiming mass produced products like shirts and jeans are just as distinct as fingerprints and DNA.

A bank robbery trial 16 years ago was a watershed for such testimony. Prosecutors charged an ex-convict with robbing a string of banks across South Florida over two years. Richard Vorder Bruegge, an FBI image examiner, told jurors that the button-down plaid shirt found in the defendant’s house was the exact shirt on the robber in black-and-white surveillance pictures. The examiner said he matched lines in the shirt patterns at eight points along the seams.

The prosecutor asked Vorder Bruegge what were “the odds in which two shirts would be randomly manufactured by the company, having all those eight points of identification lining up exactly the same?”

Only 1 in 650 billion shirts would randomly match so precisely, Vorder Bruegge said, “give or take a few billion.”

The following image — used in court to send Wilbur McKreith to prison for 92 years — was part of the FBI’s collection of circumstantial evidence, which included seeing McKreith’s vehicle near some banks that were robbed and McKreith spending around $10,000 in cash around the time of the robberies.

Where Vorder Bruegge got his “1-in-650-billion” estimate, no one knows. There’s is no body of work — at least, not outside of the FBI — on clothing pattern matching. There’s no data available detailing the number of identical shirts created during manufacturing runs or how many variations an examiner should expect to find in a lot of manufactured clothes. Nor is there any specific training required to turn an FBI examiner into an expert on clothing features. From what’s been obtained by ProPublica, the only requirement appears to be a functioning pair of eyes.

After Congress passed a law in 1968 requiring banks to have security equipment, most banks installed surveillance cameras. Meanwhile, Eastman Kodak sold the public millions of pocket-size cameras and amateur photographers took billions of exposures of life and, occasionally, of crimes.

Pictures flooded the bureau as evidence. The lab formed a team called the Special Photographic Unit to find information in images and manage the bureau’s inventory of 35 mm cameras. No scientific background or advanced degrees were required.

Unlike other areas where examiners focused on one thing (fingerprints, bullet casings, hair), “image examiners” looked at everything: facial features, clothing, and anything else that might help them make a match. But how much of a match? The FBI was trying something new, using low-quality photos and some unscientific hunch that clothing, ears, freckles, etc. were unique. As of 2005, the FBI still wasn’t offering any formal courses to train its “image examiners,” despite claiming in court shirts and jeans were as unique as fingerprints.

Like anything else, this “science” is prone to confirmation bias. But in these cases, it’s much worse. FBI image examiners aren’t given control images or items to guard against this. They’re only given images and the items investigators believe are evidence, so it guides examiners to inevitable conclusions. The “research” tends to be little more than finding ways images and items match, working backwards from the assumption the item being examined is evidence of a criminal act.

Since the FBI is considered to be staffed with the smartest and most technically-astute investigators and examiners, courts generally have granted deference to their testimony in court, even when they make claims of scientific certainty that can’t possibly be true. The examiner/expert claiming mass produced shirts were unique also claimed mass produced denim jeans were unique, in direct opposition of what’s known about mass production.

[Vonder Bruegge] wrote that manufacturing defects like dropped stitches, where a stitch is missing, are identifying features — the equivalent of a facial scar.

Not at all, said Alicia Carriquiry, director of the Center for Statistics and Applications in Forensic Evidence and an Iowa State University professor. Sewing machines can drop stitches in a consistent manner, embedding the same set of stitches in garment after garment.

“This could be that the same sewing machine in China is producing a drop stitch in the same position in every last pair of jeans until they change that needle,” Carriquiry said. Thousands of pairs of jeans would have the same feature.

The barcode pattern is unique because the stitching varies between pairs, Vorder Bruegge wrote.

But jean manufacturing has been standardized across the industry for a long time, said Charles Jebara, chief executive of Alpha Garment, which sells jeans under Nicole Miller and other labels. The number of stitches per inch along a seam is much the same from one factory floor to another. “They’re using the same kinds of machines, the same general processes to get that operation done,” Jebara said.

The supply chain for denim jeans is so standardized the FBI no longer does fiber comparisons for denim fibers recovered from crime scenes. And yet, the FBI’s champion of image examining claims [PDF] wear marks and creasing in jeans is unique enough to act as supporting evidence in criminal trials.

This isn’t science. This is jargon-laden hunchery masquerading as evidence. And despite the DOJ’s vows to dial back statements of certainty from its experts, people are still going to jail because someone with no specialized training said a pair of jeans is more distinct than a DNA strand.

Filed Under: clothing, doj, fbi, forensics, mass production