Fresno – On Wednesday, May 22, at 9 am, the Electronic Frontier Foundation (EFF) will argue that criminal defendants have a right to review and evaluate the source code of forensic DNA analysis software programs used to create evidence against them. The case, California v. Johnson, is on appeal to a California appeals court.

In Johnson, the defendant was allegedly linked to a series of crimes by a software program called TrueAllele, used to evaluate complex mixtures of DNA samples from multiple people. As part of his defense, Johnson wants his defense team to examine the source code to see exactly how TrueAllele estimates whether a person’s DNA is likely to have contributed to a mixture, including whether the code works in practice as it has been described. However, prosecutors and the manufacturers of TrueAllele claim that the source code is a trade secret and that the commercial interest in secrecy should prevent a defendant from reviewing the source code—even though the defense has offered to follow regular procedure and agree to a court order not to disclose the code beyond the defense team.

EFF is participating in Johnson as amicus, and has pointed out that at least two other DNA matching programs have been found to have serious source code errors that could lead to false convictions. In court Wednesday, EFF Senior Staff Attorney Kit Walsh will argue that Johnson has a constitutionally-protected right to inspect and challenge the evidence used to prosecute him—and that extends to the source code of the forensic software.

California v. Johnson

EFF Senior Staff Attorney Kit Walsh

Wednesday, May 22
9 am

Fifth District Court of Appeal
2424 Ventura Street
Fresno, California, 93721

For more on this case:

Related Issues