After the events of the Surrender Benson episode, where Lewis tortured Benson for days with a gun, M.E. Warner (Tamara Tunie) returned to help with the DNA evidence for the case.
Another use pointed out on Movie Mistakes: “M.E. Warner explains of Lewis and Benson ‘both their fingerprints are on the gun.’
“Lewis burned his off in a particularly gruesome scene a few episodes earlier. (It was at the beginning of his arc). Only Benson’s should be on her gun.”
The lack of continuity for the DNA makes the Lewis case harder to stomach for fans as Benson’s kidnapping could possibly have been prevented.
However, could Lewis’ fingertips have healed just enough to get prints when he was processed for a second time?
Law and Order: Special Victims Unit is currently airing season 22 on NBC in the US. A UK release date has yet to be announced.