Patrick Pursley; Illinois; Forensic scientist (Ballistics expert) Daniel Gunnell revises testimony that helped convict man of murder, The RRStar reports..."Daniel Gunnell, now an assistant director of the Illinois State Police Joliet Forensic Science Laboratory, worked as a state crime lab firearms and toolmark scientist at the time of the murder trial. Gunnell concluded that bullets and two spent shell casings found at the crime scene had come from a Taurus 9 mm semiautomatic pistol recovered from the apartment of Patrick A. Pursley - a man sentenced to life in prison but who has for years proclaimed his innocence. Gunnell testified at the time that microscopic markings on the recovered bullets and shell casings, compared with test-fired bullets and casings, showed they had been fired by Pursley's Taurus handgun "to the exclusion of all others." New tests have called Gunnell's 1994 testimony into question. Gunnell today said he had revisited the evidence himself in 2012. He still maintains the shell casings were more than likely fired by that particular gun. But his new review of the bullets - which is consistent with the conclusions of a new court-ordered examination of the evidence by the state crime lab - were inconclusive; Gunnell now says there is not enough evidence to prove conclusively that the Taurus fired the bullets, but neither could the gun be eliminated as the weapon that fired them. And Gunnell said that even if he had reached the same conclusions as he did in 1994, he would no longer describe the evidence the way he did then because of changing industry standards. Instead, he would tell jurors that his tests had concluded the bullets matched to a "reasonable degree of scientific certainty." The testimony was so strongly worded in 1994 that it denied Pursley a fair trial and "turned a weak and collapsing case based on circumstantial evidence into a case purportedly built upon a solid forensic foundation," Pursley's lawyers, Steven Drizin and Andrew Vail, told McGraw in their written post-conviction petition."

Gunnell testified at the time that microscopic markings on the recovered bullets and shell casings, compared with test-fired bullets and casings, showed they had been fired by Pursley's Taurus handgun "to the exclusion of all others." New tests have called Gunnell's 1994 testimony into question.
Gunnell today said he had revisited the evidence himself in 2012. He still maintains the shell casings were more than likely fired by that particular gun. But his new review of the bullets - which is consistent with the conclusions of a new court-ordered examination of the evidence by the state crime lab - were inconclusive; Gunnell now says there is not enough evidence to prove conclusively that the Taurus fired the bullets, but neither could the gun be eliminated as the weapon that fired them. And Gunnell said that even if he had reached the same conclusions as he did in 1994, he would no longer describe the evidence the way he did then because of changing industry standards. Instead, he would tell jurors that his tests had concluded the bullets matched to a "reasonable degree of scientific certainty." The testimony was so strongly worded in 1994 that it denied Pursley a fair trial and "turned a weak and collapsing case based on circumstantial evidence into a case purportedly built upon a solid forensic foundation," Pursley's lawyers, Steven Drizin and Andrew Vail, told McGraw in their written post-conviction petition. Pursley insists he is innocent in the slaying of 22-year-old Andrew Ascher, who was shot and killed during an attempted armed robbery.........Pursley for years unsuccessfully appealed his conviction. Then, after a 2007 change in the law, an appellate court finally sided with Pursley and ordered the ballistic evidence be re-examined. Now, with the help of the Center on Wrongful Convictions at Northwestern University and lawyers from the Chicago-based law firm Jenner & Block who took his case for free, Pursley is asking McGraw to overturn his conviction and set him free or order a new trial. Vail said that a third day of testimony would proceed Wednesday. McGraw is then expected to set a date for closing arguments."