In the US justice system, a citizen who is accused of a crime is (in theory) granted the right to a fair trial. An attorney will be provided by the government if he can’t afford one, he is not allowed to be held for indefinite amounts of time before his case is heard, and he has the right to face his accuser… unless that accuser is a piece of proprietary software, in which case it remains a deeply shrouded, legally protected secret.



And that doesn’t sit well with many legal and tech advocates.

So much of our forensic science relies on proprietary software, for everything from hair follicle matching to bite mark patterns to DNA testing. As one now thrown out case in the US has proven, even breathalyzer technology runs on software, programs which have been proven to have “bugs” just like any other software can. And just as software developers and publishers have proven, these bug fixes are routine. The difference is when your smartphone’s OS has a bug, you can’t open Candy Crush; when the state lab uses software that contains a bug, not only can you be convicted of first degree murder and sentenced to death, you’re not allowed to investigate the source code to look for the bug (or have your attorneys bring in experts to investigate).

According to Rebecca Wexler for Slate, “Coding errors have been found to alter DNA likelihood ratios by a factor of 10, causing prosecutors in Australia to replace 24 expert witness statements in criminal cases. When defense experts identified a bug in breathalyzer software, the Minnesota Supreme Court barred the affected test from evidence in all future trials. Three of the state’s highest justices argued to admit evidence of additional alleged code defects so that defendants could challenge the credibility of future tests.”

Why this investigative secrecy? Software developers claim that releasing the software could cost them money if the expert steals the code.

Yes, the court system has decided that the risk of a subpoenaed expert investigating a piece of software, then turning around and building his own startup to try to sell that software as a competitor product, outweighs the rights of a citizen who is facing the criminal penalties. Four states have already made similar rulings that the defense can scrutinize the forensic expert who determined things like DNA matches connecting the defendant to the crime, but cannot investigate the software that the expert used to make the determination.

While this has troubled legal advocates for some time, the recent news about Volkswagen’s emissions-cheating software has raised new concerns. Even government auditors aren’t allowed to see the source code in a lot of industry software, and instead have to rely on trying it out repeatedly to determine whether or not it produces valid results. Legal experts are revisiting their long-held concerns about the way we let “secret” software determine the fate of citizens.