OKLAHOMA CITY (AP) — A judge on Monday set a May 21 preliminary hearing date to determine whether convicted Oklahoma City bombing conspirator Terry Nichols should be tried on state murder charges.

State District Judge Ray Dean Linder said he wants to conclude the hearing by June 15. Nichols is charged with 160 counts of first-degree murder in the April 19, 1995, bombing of the Alfred P. Murrah Federal Building, which resulted in 168 deaths.

The date was set after defense attorney Brian Hermanson said he would not be ready by a suggested hearing date of May 7. Hermanson also said it would be inappropriate to begin May 17, because it would be the day after the scheduled execution of convicted Oklahoma City bomber Timothy McVeigh.

"We're talking about a delay of at most two weeks," Hermanson said. "The two weeks mean a significant amount to us."

Hermanson also said he is appealing Linder's refusal last month to dismiss the charges. Nichols claimed he should not be tried on state charges because he's already been convicted and sentenced in federal court.

A federal jury convicted Nichols, 46, of eight counts of involuntary manslaughter and of conspiracy. Oklahoma prosecutors are seeking the death penalty.

Linder previously denied a motion by Nichols to stay the case until the appellate court can review his ruling.

Nichols' eight federal convictions involve the deaths of federal law enforcement officers. The 160 state charges involve all the other deaths.

The preliminary hearing date will be Nichols' third since he was brought to Oklahoma last year from a federal prison in Colorado, where he was serving a life sentence.

An Aug. 7 date was abandoned after prosecutors moved to disqualify the original judge. The second date, Oct. 9, was set aside after defense attorneys moved to disqualify a prosecutor for violating a gag order and being too close to victims. The judge and prosecutor were removed.