A look at efforts to scrutinize TrueAllele's secret algorithm, which US prosecutors are using to assess the likelihood of a suspect's DNA in a mixed sample (Justin Jouvenal/Washington Post)

Justin Jouvenal / Washington Post:
A look at efforts to scrutinize TrueAllele's secret algorithm, which US prosecutors are using to assess the likelihood of a suspect's DNA in a mixed sample  —  The Exxon clerk never got a good look at the assailants who robbed him at gunpoint in Fairfax County, so investigators hoped to bolster …