The trial for Davidson, the alleged ringleader in the Christian-Newsom murders, is scheduled to begin October 19.
The new evidence suggests DNA found in Channon Christian's underwear doesn't match any of the defendants, her boyfriend Chris Newsom or a man convicted as an accessory in the case, Eric Boyd.
However, the test does indicate the DNA is from two unidentified men.
Two other motions filed by the attorneys seek to dismiss the case.
One motion claims police violated attorney client privilege by intercepting a letter from Davidson to his lawyer.
The other claims the death penalty goes against the state constitution.