http://articles.latimes.com/2010/apr/09 ... -2010apr09
OpinionThe dangers of growing DNA databases
April 09, 2010|By Osagie K. Obasogie
President Obama may have given credence to a relatively new but questionable law enforcement practice that the rest of the developed world is starting to shun: taking and retaining DNA samples from individuals arrested for a crime but not convicted. That is, putting innocent people's DNA in criminal databases.
Take, for example, a 2005 examination of Arizona's criminal database. The entire enterprise of DNA databases is based on the idea that no two people share the same profile. But Arizona's database of 65,000-plus entries was shown to have more than 100 profiles that were similar enough for many experts to consider them a "match."
In separate studies, it has been reported that Illinois' and Maryland's databases had hundreds of seemingly unique genetic profiles matching one another. This is a phenomenon that suggests people convicted solely on evidence from DNA databases may have profiles that coincidentally match the real perpetrators', leading innocent people to be incarcerated. Or worse.
How is this possible? We simply don't know, in part because state and federal officials have stonewalled scientists' request to study these databases.