E-Mail This Article to a Friend BAD BALLISTICS Federal judge KOs BPD’s "expert" testimony BY DAVID S. BERNSTEIN

James O’Shea is as good as the Boston Police Department has for matching bullets and shell casings to specific firearms. He has been in the ballistics unit for seven years, supervises others, and has testified in hundreds of cases. So it was a major blow to the department when a federal judge prohibited O’Shea from telling a jury that he found a match between a gun and shell casings found at a crime scene.

"That conclusion — that there is a definitive match — stretches well beyond O’Shea’s data and methodology," wrote Judge Nancy Gertner last Thursday, in a ruling on a pretrial motion in an alleged-gang-shooting case. As a result of Gertner’s decision, O’Shea was allowed to describe only the similarities and differences he saw when he examined the ballistics evidence against Jonathan Hart and Edward Washington. He could not state his conclusion that the casings must have come from the gun in question.

Gertner’s ruling "is a momentous decision," says Joan Griffin, a Boston attorney who recently won a similar decision from Judge Patty Saris, also of the US District Court, in a case centering on a member of the Massachusetts State Police ballistics lab who will testify against her client, defendant Angelo Brandao. "To my knowledge," says Griffin, "[Gertner] and Saris are the first judges in the country that have excluded any portion of ballistics testing."

Both rulings question the underlying reliability of ballistics testing, but also specifically fault the shaky methods and standards used by local labs. In her decision, Gertner wrote that O’Shea never had his proficiency formally tested; could cite no reference materials or databases he used as resources; did not contact the gun manufacturer for information about the firearm’s distinctive features; took no notes, recorded no measurements, and drew no diagrams; did not follow existing protocols; and examined the evidence with knowledge that he was handling the suspected gun, rather than putting the weapon through a scientifically blind test. And when he was asked what standards he used to determine that the markings supported the conclusion of a match, Gertner wrote, "O’Shea’s testimony was either tautological or wholly subjective."

The ballistics decisions could affect hundreds of cases coming before both federal and state courts in Massachusetts. Most immediately, they will have a huge effect on high-profile related cases coming before the same judges. Hart and Washington are two of the alleged "Esmond Street Crew" members arrested in 2000; two of the other defendants, scheduled for trial next year, are eligible for the death penalty if found guilty. Brandao is one of a large group of defendants — two of whom were considered for death-penalty charges — also scheduled for trial next year. (The US Attorney’s Office, which is prosecuting these cases, will not comment on the Gertner and Saris rulings while the cases are ongoing.)

All these cases involve lots of ballistics evidence, and will be much harder to prove if BPD and state experts are prevented from claiming that the bullets and casings must have come from the specific firearms in evidence.

O’Shea’s testimony revealed something else of note: he claimed that, while he had never been formally tested for proficiency, he had taken such a test "informally" at the department on at least one occasion, and that his results were compared against results of another examiner. The BPD has admitted, in response both to a Boston Phoenix public-information request and to recent court orders, that it has given only one firearm-comparison-proficiency test to one examiner in the past 10 years, which was submitted to a testing service for grading.

But O’Shea is now the second member of the ballistics team to contradict that claim. As the Phoenix reported in October (See "Bad Ballistics," News and Features, October 7), Tyrone Camper testified in a pre-trial hearing in Suffolk Superior Court that he had been given several proficiency exams by his former supervisor, Mark Vickers. Camper also testified that he failed some of these tests. Which begs the question of why the rest of the BPD never heard about the results.

Meanwhile ... local forensics experts got slapped with yet another ruling this week, this one from the state’s Supreme Judicial Court, concerning fingerprint testimony. In that case, fingerprints from four fingers were found, but none of them had enough "points of similarity" to meet the standards for a match against any of the fingers of Terry Patterson, who is accused of killing Boston Police detective John Mulligan, in 1993. But the BPD expert — who worked in the latent print lab before it was shut down in 2004 — testified at Patterson’s murder trial that the prints were Patterson’s, because the points of similarity on all four prints, added together, met the standard for a match. In this week’s ruling rejecting that claim, the SJC pointed out that no other US agency or jurisdiction uses this add-’em-up theory, "save for the now disbanded Boston police fingerprint unit and the [Massachusetts] State police."