It was a run of the mill drug slaying. The victim, Van Reaves, 41, was beaten and shot to death in his Temple Hills apartment over a $200 cocaine debt, investigators said. Police locked up two suspects within three weeks of the March 5, 1998, slaying. One of them signed a statement admitting to the shooting.

But the attempts by prosecutors from the Prince George's County state's attorney's office to bring the alleged killers to justice have been anything but routine.

Sixteen months after the slaying, one of the two suspects has been acquitted. Prosecutors are preparing to try the other suspect, Dion Johnson, 27, the accused trigger man, for the fourth time. Twice his case has ended in a mistrial, the most recent occurring Thursday. In the third instance, there was a last-minute continuance.

The trial has been rescheduled for Dec. 13.

The most recent attempt to try Johnson ended in a bizarre fashion--Johnson agreed with the prosecutor that the case should go forward while his own attorney sought a mistrial over a witness statement and requested a psychiatric exam to determine Johnson's mental competence.

It's a case that no one seems to be able to finish.

"It's becoming a nightmare," said David M. Simpson, Johnson's attorney.

"I'm not happy," Assistant State's Attorney Roland Patterson said.

"I'm angry," said Sarah Johnson, Dion Johnson's aunt. "There seem to be a lot of mix-ups with this prosecutor."

When Johnson arrived in the courtroom of Circuit Court Judge Theresa A. Nolan on Thursday, he fully expected to take the stand to testify in his own defense. He became enraged when Simpson asked Nolan for a mistrial because a prosecution witness revealed that Johnson had a codefendant in the slaying who already had been acquitted.

The statement by the witness, James Toth, made it impossible for the trial to continue because information about the codefendant had the potential to sway the jury.

Toth testified that he talked to Johnson and the other man who had been charged in the slaying, Farad "Rico" Mohammed, 24, about the killing just after it happened. Toth testified that Johnson and Mohammed described their roles in the killing.

During Simpson's cross-examination, Toth said he was afraid of Mohammed. Toth said he was so afraid of Mohammed that he stabbed a woman, a witness against Mohammed, when Mohammed ordered him to. Mohammed also threatened him with a gun, Toth said.

Simpson's defense of Johnson was based on the theory that Mohammed was responsible for the Reaves slaying and that Johnson was afraid of Mohammed and that fear prompted Johnson to admit to the shooting.

On redirect examination, Patterson asked Toth what effect his fear of Mohammed had on his testimony.

Toth testified that his fear had not affected his testimony, then went further: "I testified against [Mohammed] in his case." After a brief pause, Toth continued, "Hopefully, I'll never see him . . . he got off."

A short time later, Nolan declared a mistrial after Simpson asked for one. It was an ignominious end to a difficult time on the witness stand for Toth. He had claimed not to know details about a deal with prosecutors in which he would be sentenced to no more than four years in prison for stabbing the witness against Mohammed, Debra Nelson.

Under Simpson's cross-examination, Toth also testified that he didn't know exactly what charges he faced for the stabbing and how much time he faced. He also admitted that in his first statement to police, he claimed he stabbed Nelson when she tried to rob him.

Toth also had a difficult time on the witness stand in Mohammed's trial, which began in late March and ended in acquittal in early April.

Nikki Lotze, Mohammed's defense attorney, had Toth reenact his attack on Nelson in front of the jury, with Lotze playing the role of the victim.

Like Simpson, Lotze also hammered away at the deal prosecutors made with Toth for his testimony.