In the closing days of the mayor's trial, chief defense lawyer R. Kenneth Mundy is employing a new maneuver that some strategists expected long ago: For the first time, he is playing against the judge and casting him as a partisan in the case.

Like many of Mundy's tactics, it is unspoken and indirect. But there is nothing subtle about it.

Three times in two days, Mundy has provoked a confrontation, all but daring the judge to slap him down in front of the jury. Twice -- once yesterday and once Tuesday -- U.S. District Judge Thomas Penfield Jackson rose to the bait. But when Mundy appeared to try it a third time yesterday, Jackson smiled, cocked his head, and let the moment pass.

The message that Mundy apparently wants conveyed is a variation on the defense's central theme, that there is a government vendetta against Mayor Marion Barry. Not only the FBI but the whole federal apparatus, Mundy seems to be suggesting, is aligned against his client in this case.

"The fact that {Jackson} is white . . . and he appears to be assisting the prosecution shows the white establishment against the black defense team," said Kenneth Robinson, a local defense lawyer who has consulted with Mundy about the mayor's case. "The longer the trial goes, the more short-fused the judge gets."

Mundy, unlike Robinson, does not have a reputation on the local bench for baiting a judge for tactical advantage. Judges interviewed recently who have presided over his trials say they have never seen Mundy use the strategy in court.

But the judges and other strategists agreed: A lawyer with Mundy's sense of theater does not provoke reprimands without a purpose.

"Anything that Mundy does, he has a reason," one judge said last night. "He does not do things by accident."

Mundy's method of operation could not be simpler: He begins a provocative line of questioning aimed at piquing the interest of the jury, then continues to ask similar questions after Jackson has asked him to stop.

There were feints in that direction as early as the first week of evidence, but the tactic did not make its debut until Charles Lewis returned to the witness stand Tuesday.

Mundy wanted to intimate that Lewis had an unsavory relationship with four Virgin Islands women who corroborated Lewis's testimony against the mayor. At the bench, Jackson ordered him to limit his line of questioning in that regard. When Mundy continued aggressively, Assistant U.S. Attorney Judith E. Retchin stood to object.

"Sustained," Jackson said, a tone of reproval in his voice.

"Your honor, may we approach the bench?" Mundy asked.

"Sustained," Jackson replied, shaking his head angrily at the request. "Sustained. Move on."

Mundy did not move on, instead asking a nearly identical question. Jackson again sustained Retchin's objection. Six questions later, Jackson sustained another Retchin objection, and again Mundy rejoined by repeating the question. This time the judge did not wait for the prosecution to object.

"Approach the bench," he ordered angrily. The jurors could not hear the words, but Jackson visibly was scolding the lawyer in the bench conference that followed. Mundy's face was all injured innocence upon his return.

Late yesterday morning, Mundy raised the temperature a second time. The subject was prosaic -- alleged discrepancies in an FBI agent's account of his custody of evidence -- but Mundy used his tone and body language to signal that he had the agent on the run. Prosecutor Richard W. Roberts objected. "Argumentative and repetitive," he said.

"Sustained," Jackson replied.

Mundy asked a similar question.

"Same objection," Roberts said.

"Sustained," Jackson replied.

Again Mundy asked the question.

"Sustained," Jackson said irritably. "Move on, Mr. Mundy."

Mundy, "with due respect," then asked to approach the bench. Again the jurors could see Jackson scolding him. Mundy raised his voice, and fragments of his replies were audible. Still at the bench, Roberts and Mundy had an angry exchange. Jackson said, "Gentlemen! Gentlemen!"

In the afternoon, Mundy again embarked down this path. Jackson sustained two objections. Mundy asked the question again. But this time the judge did not grow angry. Smiling and shaking his head, he overruled the objection.

"Go ahead," Jackson said, with just a trace of weariness in his voice.

Staff writer Michael York contributed to this report.