Since it was first tried earlier this year, the case of former Ballou High School counselor John T. Jones has hardly been a model of lawyerly civility. As his retrial on charges of sexually assaulting or enticing three students neared a conclusion yesterday, the tone turned snippy.

In closing arguments that spanned nearly three hours, the prosecutors and defense attorneys took shots at each other's cases and at each other as a standing-room-only crowd in D.C. Superior Court looked on.

In tone, the current trial is much like the first, which ended in March with the jury acquitting on some charges but deadlocking on most. But in at least a couple of key aspects, this trial, which began almost three weeks ago, has been markedly different.

Most significantly, the judge in the case, Ann O'Regan Keary, reversed a key ruling from the first trial and allowed the testimony of a woman who had accused Jones of raping her in 1992. That investigation had languished until 1996, when charges were filed; a 1997 trial ended in a hung jury, and prosecutors elected not to retry the case.

The prosecution successfully argued that the woman's testimony could show that Jones, 39, has an unusual sexual preference. The woman was 15 when Jones allegedly assaulted her, the same age the principal accuser in the current case was during many of her alleged encounters with Jones.

Late yesterday, the jurors began weighing the case, and while they are not supposed to consider the woman's testimony as evidence of any pattern or mode of operation, the account of a similar incident years earlier could be significant.

Jones was working as an attendance counselor at Ballou, his alma mater, when the charges were lodged against him last year. Prosecutors charged that he used his authority to pursue girls he lusted after.

By contrast, lead attorney Jonathan A. Rapping of the D.C. Public Defender Service portrayed Jones as a loving husband victimized by vindictive, troublemaking students.

"You either believe them or you don't," Rapping said of the three girls. "That's what this case is about."

In the first trial, jurors could not agree on whether to believe the accusers, and the girls' accounts remain replete with inconsistencies. In his closing, Rapping laid them out alongside some of the girls' potential motives to lie.

One of the girls, Rapping said, had cheated on her girlfriend and contracted a sexually transmitted disease. Rather than admit her infidelity, she seized on rumors of indiscretions by Jones and accused him of sexually assaulting her, Rapping said. "She came up with a story that would make her look more sympathetic," Rapping said.

But in rebuttal, one of the prosecutors, Assistant U.S. Attorney Geoffrey A. Barrow, said that if the girls were going to lie, they would have been far more elaborate and dramatic. The inconsistencies cited by Rapping were "natural" and inconsequential, he said.