CSI DDS | Forensic Science Testimony. CSI bad science issues and their contribution to wrongful convictions.
Sunday, December 4, 2016
Santa Clara County crime lab: California; The Mercury News (reporter Tracey Kaplan) delves into doubts which have emerged about a forensic test - a semen test known as p30 - that could undermine dozens of sex cases. (Here we go again? HL)..."The county’s crime lab director insists the problems have cropped up only recently. But forensic scientists have long raised questions about the semen test’s accuracy, which prompted Contra Costa and Los Angeles counties to stop depending on it as solid proof of sexual assault at least 12 years ago. And privately, in an Oct. 16 email intended to be seen only by other crime lab directors in California, Santa Clara County’s director Ian Fitch expressed alarm about the situation, saying his bosses in the District Attorney’s Office were worried that erroneous or unreliable test results may have put an innocent person in prison or require dozens of cases to be reopened. “Our DA’s Office is freaking out,” Fitch wrote, “concerned that they’ve convicted someone as a result of the lab falsely reporting the confirmed presence of semen.” Abacus Diagnostics, the semen test’s only manufacturer, based near Los Angeles, did not respond to repeated requests from this newspaper for comment."..."In the past 14 years, the test, known as the “p30,” may have played a role in two to four cases a year — for a total two to five dozen Santa Clara County sexual assault cases, Angel estimated. The test can be key in relatively rare and potentially more difficult-to-prove cases where forensic experts seek to find evidence of a man’s seminal fluid with the victim or at the crime scene, but cannot detect his sperm, which would identify him through his DNA. Concerns about the test have reignited calls by the defense bar for greater independence of crime labs, which are typically run by law enforcement agencies such as the District Attorney’s Office, sheriff’s offices or police departments. The primary problem with the test is that it can erroneously indicate the presence of semen where none exists. “False-positive” results can occur because even though the test is designed to detect an antigen found in semen, smaller concentrations of the antigen also can be found in other substances, such as fecal material and female urine. As a result, some labs, including Contra Costa County’s since 1999, have long treated the test as presumptive, or a probable sign of semen, rather than solid proof. However, Santa Clara County only reclassified it as presumptive for tests conducted after Feb. 2 after coming across false-positive results last year. Local public defenders and some forensic scientists criticize the start date as arbitrary."..."Santa Clara County’s other problem with the test — in the pending capital case — was its own fault. The crime lab acknowledged in a memo to the District Attorney’s Office that an analyst performed the test incorrectly in the death penalty case against Alejandro Benitez, who is charged with the 2012 murder of a 17-month-old San Jose boy. The test is most commonly performed on diluted dried semen. But in the Benitez case, the analyst tested the victim’s stomach contents without diluting it, which produced what the lab learned recently from the manufacturer was a false-positive result for semen, according to court documents. The county’s medical examiner relied heavily on the test to conclude the victim died from “lack of oxygen caused by probable oral copulation.” Prosecutors still are pursuing the death penalty because they are confident they’re are right about what happened to the child based on other evidence analyzed by the crime lab and the medical examiner’s autopsy indicating the child was sexually abused. But one of Benitez’s attorneys, Alternate Public Defender Jessica Delgado, claims the lab’s mistake is “at the center of confirmation-biased investigation by law enforcement,” buttressed by forensic analysis that is “anything but objective."..."But Benitez’s attorneys are hoping to uncover more embarrassing information from the crime lab if they succeed in persuading a judge to order the District Attorney’s Office to release more internal documents and emails concerning the semen test. The court has already granted Delgado’s request to block the county from destroying emails related to the case as part of a long-planned countywide purge of emails that have been in the system two years or more, though that is no guarantee of how much more will be turned over to the defense."
STORY: "Doubts about forensic test could undermine dozens of sex cases," by reporter Tracey Kaplan, published by The Mercury News on December 3, 2016. Tracey Kaplan is a reporter for the Bay Area News Group based at The Mercury News. She covers courts and has been in love with reporting for the past 30 years, including eight at the Los Angeles Times where she was part of a group that won a breaking news Pulitzer for coverage of the 1994 Northridge quake. (Thanks to Dr. Michael Bowers of Forensics in Focus CSIDDS for bringing this story to our attention. HL);