The judge in the O.J. Simpson armed robbery and kidnapping case ordered a man to be brought to court with a recording that may contradict sworn testimony from a key witness against Simpson.

Lawyer Robert Lucherini told Clark County District Court Judge Jackie Glass on Thursday that he heard Kevin Mikell, a former client of his, play an audio recording in which Michael McClinton contradicts testimony he gave in a preliminary hearing in November.

McClinton testified that Simpson directed him to bring guns to a confrontation with two sports memorabilia dealers at a Las Vegas casino hotel room last Sept. 13. McClinton testified he wielded one of the weapons after Simpson told him, "Show them your weapon and look menacing."

Outside court, Lucherini estimated the recording lasted about 15 minutes, but he refused to recount what was said or specify what parts of McClinton's testimony it contradicted.

"I heard enough of it to know it was extremely exculpatory," Lucherini said.

McClinton's account could be crucial for prosecutors to try to disprove Simpson's claim that no guns were displayed, and that he never asked anyone to bring guns, didn't know anyone had guns, and only intended to retrieve keepsake items he claimed were stolen from him.

Lucherini said Mikell, who he said was a one-time friend of McClinton, wouldn't let him keep the recording or make a copy, and now won't respond to his telephone calls.

Prosecutor Chris Owens told the judge that investigators also hit "a block wall" trying to reach Mikell.

"Let's see if you can subpoena him to be here for a hearing on the 25th," Glass told Owens, referring the next pretrial hearing she scheduled Aug. 25. "We're going to see what we can do about the mysterious Mr. Mikell."

Mikell did not immediately respond to a telephone voicemail message from The Associated Press.

Simpson, Clarence "C.J." Stewart and Charles Ehrlich are due to stand trial Sept. 8 in Las Vegas on kidnapping, armed robbery and assault with a deadly weapon charges that could put them in prison for life if convicted.

McClinton, 50, originally was charged in the case but took a plea deal.

Lucherini, who represents Stewart, said he represented Mikell in a 1997 criminal case in which court records show Mikell pleaded guilty to aiming or discharging a firearm at another person, and was sentenced to six months in county jail.

Simpson lawyer Gabriel Grasso said if a recording surfaced that diminished McClinton's credibility, it would help all three defendants.

"I think it would help everybody because McClinton is one of the main witnesses against O.J.," Grasso said.

In court, Glass said she expected to spend all day Aug. 25 on Simpson case pretrial matters.

She told lawyers to be prepared for a closed-door session to sift through responses from 400 or more prospective jurors to a 26-page, 116-question questionnaire she completed Thursday.

"This questionnaire is confidential," the judge declared. "It is not to be released or discussed with anyone."

Glass also said she intends to hold the trial in her regular courtroom, which has 46 seats for the public, instead of a larger venue. Earlier hearings in the case have been held in a courtroom with more than 100 seats.

"The court prefers to hold the trial here," Glass said.