The Texas district attorney who was to prosecute for a second time the man whose murder conviction inspired the movie "Bernie" has asked to recuse himself on the eve of a pretrial hearing, saying he's become a witness.

In a motion filed Monday in state district court in Carthage, Danny Buck Davidson asked to recuse himself and other prosecutors in his Panola County District Attorney's Office from the Bernie Tiede (TEE'-dee) case.

Tiede was convicted of killing wealthy widow Marjorie Nugent and storing her body in a freezer. He was released from prison after a judge agreed to reduce his sentence. Davidson agreed the former mortician was wrongly sentenced to life imprisonment.

Davidson did not specify how he was a witness. He asked that a special prosecutor be appointed.