Every state now has a legal avenue where people can request DNA testing of evidence after being convicted. But in many cases, it’s not clear if those statutes apply once convicts have died, said Brandon Garrett, a law professor at Duke University.
Posthumous exonerations based on DNA testing are exceedingly rare. There are only seven such cases across the nation over the past three decades, according to a database maintained by Garrett.
But there is always the possibility of more, and Tanner’s case could help pave the way. The advent of DNA testing “upended all these traditional notions of finality,” Garrett said. “As long as it’s kept in a dry place, you can test it 60 days later or 10 years later.”
