Sharp, of the 4th Judicial District in Ouachita Parish, found that Duncan’s conviction was based in part on bite mark evidence now considered by experts to be junk science. That original analysis came from forensic dentist Michael West and pathologist Dr. Steven Hayne, whose longtime partnership as state experts has been questioned following concerns about the validity of their techniques. West, who did not respond to previous requests for comment, admitted in a 2011 deposition in another case that he no longer believed in bite mark analysis. Hayne died in 2020.

Over the past 27 years, nine prisoners have been set free after being convicted in part on inaccurate evidence given by West and Hayne. Three of those men were on death row. Duncan was the last person awaiting an execution based on the pair’s work.