ROAD TOWN, British Virigin Islands — A sort of trial within a trial — to determine whether prosecutors presented enough evidence linking four men to the killing of Lois McMillen — is being interrupted Thursday afternoon so Justice Kenneth Benjamin can decide whether to declare a mistrial.

The sudden shift in the case came Thursday morning after two jurors left the grounds of Eastern Caribbean Supreme Court to run errands. The two jurors were accompanied by a police officer.

Under the British court rules, the nine jurors hearing evidence in a case are required to remain together while court is in session.

The jury has been sequestered in a back room since Tuesday afternoon, when lawyers for defendants William Labrador, Michael Spicer, Alexander Benedetto and Evan George, began lengthy dismissal motion arguments. The men are charged with killing Lois McMillen, 34, by drowning in January 2000.

The judge discovered the jurors were missing at about 11:40 a.m. when he called the jury back to the courtroom to dismiss them for a long lunch break.

The two jurors and police officer returned about 15 minutes later. One of the jurors told the judge that she misunderstood his instructions and left with another juror to run an errand.

Benjamin said he will hold a hearing Thursday afternoon and will decide whether the infraction was a small one or one making it necessary for him to "abort" the trial, now in its seventeenth day.

"Don't worry about it. He had to say that," Benedetto, 35, told a friend in the gallery who looked concern that the whole process might have to begin again in the fall.

Benedetto and the other defendants, all friends or acquaintances of McMillen, an eccentric artist from an affluent Connecticut family, are accused of killing the woman after one of the men allegedly had an argument with her over money. A prison informant testified that Labrador confessed, but very little testimony was offered through prosecution witnesses about Benedetto's alleged role.

Benedetto's lawyer, Paul Dennis, finished his argument that the prosecution presented no case through its 24 witnesses for Benedetto to answer. "There is no evidence," Dennis repeated over and over while on his feet for two hours.

"My Lord, that is the totality of the Crown's evidence. In that testimony there is no evidence that this accused committed the crime alleged," Dennis said. "It is so very tenuous, so very vague and unreliable that no jury, properly directed, could convict upon it ... It cannot yield a lawful conviction."

The prison informant, Jeffrey Plante, testified that Benedetto and Labrador argued constantly in Her Majesty's Prison about who was more guilty. Benedetto also allegedly yelled at Labrador that he was the one that had "the girl up at the house."

Dennis argued that even if the statement of Plante was believed, it was vague and not evidence of murder. Dennis raised voice each time he mouthed the word "murder."

"It is so vague as to be meaningless," Dennis argued on behalf of Benedetto. "My Lord, there is no evidence he was speaking about the deceased."

Benedetto, the son of a New York book publisher, dated McMillen for three months in 1997 but told police it ended amicably. He found McMillen strange and broke off the fling, he said in a statement. A chance meeting between McMillen, Benedetto, Spicer and George two nights before the killing was casual and friendly, according to the statement.

George, 23, told police that Benedetto confided that seeing McMillen was one of the reasons he wanted to visit this eastern Caribbean island last year. That statement is not evidence of guilt, Dennis argued, and is "worthless and of no value" to jurors."

Benedetto, who has blond hair and blue eyes, leaned over in his seat and patted Dennis' back as the lawyer sat down.

Lawyer Joseph Archibald took just 15 minutes to argue that George — whom the jury has heard very little about — should not have to present a defense to a murder charge that was not proven by the prosecution.

Going over the testimony of Plante, police and expert testimony, Archibald said that there in no confession, incriminating statements, circumstantial evidence or physical evidence to link George to McMillen's death or the rocky shoreline where her body was discovered on Jan. 15, 2000.

Wearing a dark blue suit and black rubber-soled shoes, George played with his tie during much of the protracted legal arguments about whether the trial should proceed. George, who lives in Washington, D.C., apartment owned by Spicer, is originally from Oregon and still has family there.

Archibald told Benjamin that it is time that he release George, who has been held for 468 days.

If Benjamin allows the trial to continue, prosecutors are expected to argue Thursday afternoon that many of the issues the defense lawyers raised should be decided by the seven women and two men of the jury.