David Kaye

     Professor David Kaye was interviewed on Wednesday, July 23, on KPCC Southern California Public Radio regarding criticisms about the reliability of DNA statistics in identifying crime suspects.
     Kaye's comments to Air Talk host Larry Mantle came on the heels of an article in the Los Angeles Times by investigative reporters Jason Felch and Maura Dolan that raised questions about whether the nation's databases of DNA-identification profiles of convicted offenders should be scrutinized to check the accuracy of the theoretical estimates of how rare a DNA profile is. In that article, Kaye supported such research.
     In searching for suspects, crime labs commonly attempt to compare at least 13 locations on chromosomes, or loci, which are used to distinguish people. The FBI has estimated the odds of unrelated people sharing only nine of those genetic markers to be as remote as 1 in 113 billion, according to the Times report. These compelling odds often are cited in DNA cases to suggest an all-but-certain link between a suspect and a crime scene.
     "Are these numbers believable? Some of them come in the quadrillions, the septillions, the sextillions, which means about 20 zeroes," Kaye said.
     "We need to ask three separate questions: One, is a number like 1 in 113 billion accurate, given the way it's calculated? Two, how is the jury going to deal with it, even if it is accurate? And three, what happens if you get somebody from a database versus you already have a suspect, and their DNA matches DNA from the crime scene?"
        To listen to the full interview, go to http://www.scpr.org/programs/airtalk/.