COLUMBUS -- A Roman Catholic priest serving 15 years to life in prison for killing a nun has told a newspaper that he's innocent.

The Rev. Gerald Robinson was convicted in May 2006 for killing Sister Margaret Ann Pahl in 1980 by strangling her and stabbing her 31 times in a Toledo hospital chapel.

Robinson told The Columbus Dispatch for Sunday editions that he didn't do it and that he has no idea why anyone would do it.

But Lee Pahl, the victim's nephew, said he believed at the trial that Robinson was the killer and continues to believe it.

He's also bothered that the Catholic Church hasn't defrocked Robinson.

Lawyers for the Ohio Innocence Project are continuing tests to determine whether DNA under Pahl's fingernails matches someone else.