“There is a lot of concern,” Morgan said. “People aren’t happy that it is essentially a black box.”
Cybergenetics claims the math behind the software has been disclosed, and welcomes both sides of any case to test the software on its own data. But Sue Pope, a DNA expert and co-director of Principal Forensic Services Limited, said there must be independent validation of the software itself.
“A courtroom setting is not the best place for looking at really detailed questions about how statistics have been done,” Pope said.
Yet courts around the country have upheld TrueAllele’s source code as trade secret, relying largely on a 2015 decision, People v. Chubbs, in which the defendant was found guilty after he was unable to challenge the DNA evidence because of his inability to access information about how the software works.
Juries Continue to Trust DNA as Fact
Despite its tattered history, juries continue to believe strongly in DNA evidence because of its strong foundation in science and statistics. In 2005, a Gallup poll showed 58 percent of people believed DNA evidence was “very reliable”; both juries and attorneys consider it extremely reliable. The so-called “CSI-effect” indicates that many jurors and even judges need to be convinced that the presence of the defendant’s DNA at a crime scene does not necessarily render them guilty.
And DNA evidence can be 100 percent certain under perfect conditions. Yet this rarely occurs. First, the evidence must meet the scientific standards of this large quantity of well-preserved DNA. Also, there must be no question of how that DNA arrived at the crime scene—for instance, ensuring that the DNA does not belong to an innocent person who happened to walk through the area bleeding that same day, along with every other possibility. Finally, the laboratory must handle the DNA with no errors in process or procedure.
There are no credible statistics for the number of falsely accused or imprisoned based on flawed DNA evidence.
Murphy, who was previously a public defender, told The Atlantic: “I don’t think it’s unreasonable to point out that DNA evidence is being used in a system that’s had horrible problems with evidentiary reliability.” She highlights the central issue in her book, Inside the Cell: The Dark Side of Forensic DNA: “The same broken criminal-justice system that created mass incarceration,” she writes, “and that has processed millions through its machinery without catching even egregious instances of wrongful conviction, now has a new and powerful weapon in its arsenal.”
Indeed, DNA evidence can be so powerful, it’s difficult to open people’s minds to its potential shortcomings once it’s been presented.
Hampikian talks about changing people’s minds about DNA evidence based on his experience with the Innocence Project: “I don’t think people are evil, but once they’re convinced of a story they protect it.”