"In
the trial of the accused Grim Sleeper serial killer, the prosecution has
repeatedly pointed jurors to evidence matching bullets in seven victims
with the same .25-caliber semiautomatic handgun. But as the
case edges closer to a conclusion after beginning more than two months
ago, defendant Lonnie Franklin Jr.'s attorney Seymour Amster has cast
doubt on the DNA evidence used to charge his client as well as firearm examiners' methods for matching bullets. County
prosecutors called several firearms experts to the stand in Los Angeles
County Superior Court Judge Kathleen Kennedy's courtroom before resting
their case in March. LAPD firearms expert Daniel Rubin
testified that examiners can match bullets to a gun by analyzing tool marks on a bullet after a round is fired. Because
the machine tools used to manufacture firearms leave unique marks on
the barrel, experts can determine if bullets were fired from the same
gun, the jury has heard. Rubin told jurors that he matched
bullets found in victims Debra Jackson, Henrietta Wright, Barbara Ware,
Bernita Sparks, Mary Lowe and Alicia Alexander to the same semiautomatic
handgun. The expert said his analysis confirmed that the
alleged killer's only verified survivor Enietra Washington had been shot
with the same .25 caliber handgun as Wright. But on Tuesday, defense witness David Lamagna said he believed that law enforcement's methods are unreliable. Examiners
relied on two-dimensional comparison microscopes to analyze the unique
tool marks left on bullets. But Lamagna, a forensic scientist and
engineer, said he only trusts advanced technologies like 3-D mapping or
electron microscopes that allow examiners to look at objects in finer
detail. Amster asked Lamagna if he believed the method used by law enforcement creates conclusions that leave room for doubt. "Yes. I believe it's mostly subjective in nature at this point," Lamagna said. He
noted that there had not been enough studies done to test the
reliability of the tool-mark analysis and said that a forensic
ballistics organization, the Association of Firearm and Tool Mark
Examiners, has "no mathematical standards" for deciding a match Law enforcement lacks specific protocols, he added. Lamagna said he had traveled to different police departments around the nation and seen varied standards. "I see different examiners doing their own thing," Lamagna testified. Lamagna
is the owner of American Forensic Technologies, which according to his
LinkedIn page provides "forensic review and analysis of evidence in
civil and criminal cases" as well as field investigations. Franklin
is accused of killing vulnerable young black women over a period that
began in the mid-1980s. His victims were often sex workers, and
prosecutors say he prowled the streets during the height of the crack
cocaine epidemic — killing seven women during a period that ended in
1988. Another four murders between 2002 until 2007 have been
linked to the Grim Sleeper, who earned the name because of a possible
fallow period during the late 1980s and 1990s — though it's
believed that the alleged serial killer may have killed many more women." (Thanks to CSIDDS (Forensics in Focus) for bringing this story to our attention.)
https://csidds.com/2016/04/29/back-and-forth-in-court-about-raising-technical-instrumentation-ballistic-standards/
http://www.courthousenews.com/2016/04/26/grim-sleeper-defense-picks-holes-in-bullet-analysis.htm