During a criminal trial in U.S. District Court in New York City, a juror, Virginia Stephenson, became infatuated with the prosecutor, Assistant U.S. Attorney Ira H. Block.

Once, when filing out of the courtroom with her peers, she blew a kiss toward the prosecution table.

Block won his case when the jury convicted Dennis W. Mulligan, a police detective, of prejury.

Stepenson, a trade-publication classified advertising manager described by Mulligan's laywers as middle aged and middle-class, then went to see Block in his office.

It was as if she were "in the inner office' of a candidate, whom you've worked for and believed in, at the moment of history," she recalled in a letter to Block. ". . . The thrill of just being there defied description."

A few days later, another juror, in a letter to the trial judge, Richard Owen, disclosed that he and other jurors had been unconvinced of Mulligan's guilt. But, he said they had voted to convict him on the seemingly unimportant perjury count in order to get a unanimous vote to acquit him of more serious charges, particularly bank robbery and conspiracy to commit bank robbery.

Then, in a long letter to Block, Stephenson thanked him for "letting me share in your 'victory," expressed regret that it was limited to the perjury count, enclosed her card, and said, "Please give me a call at your earliest convenience."

In addition, Stephenson praised Block for his "greatness" in having "succeeded in doing something that five years of analysis with a brilliant doctor could not do": enabling her to achieve "a complete catharsis of the soul" that restored her "self-confidence . . . I believed the fact that 11 other people said I was wrong."

Now, Stephenson went on, "I'm writing again! Eagerly. Avidly. With enthusiasm!" Her project: a planned book about Frank Smith, who had participated in the bank robbery, but who had become one of the government's two chief witnesses at the trial.

Asking Block's help, she wrote, "Ira we've got one hell of a book!" It would earn sufficent royalties so that "Frank Smith will never have to rob another bank."

The prosecutor turned the letter over to Mulligan's lawyers. Looking into Stephenson's background, they found that, in 1973, she had angrily blamed atmospheric pollution around her apartment on postal trucks at a nearby post office.

When she went to the facility to complain, two postal employes directed her to a different entrance. Trying to push past them, she scratched mail handler Joseph Scelza on the face and stabbed him in the back of the head with a ball point pen. He went to a hospital for treatment, including stitches.

Police officers charged Stephenson with a felony assault, held her overnight, and arraigned her. But Scleza, never advised when he was to appear for the arraignment, didn't show up, resulting in dismissal of the charge. Later, however, he filed a successful civil suit.

In the Mulligan case jury selection, Stephenson was asked whether she had "ever been involved in a criminal case." Her answer was, "No, sir." Although the postal employe had sued her and won, she denied having had "any dispute with the United States."

After becoming a juror, Stephenson experienced "the exhilaration of the trial," as she put it in her letter to Block. Then, when deliberations began, she alone voted for conviction. She held out for two days, until the compromise was reached.

Mulligan, on being convicted, was dismissed from the police force. He is now serving a two-year sentence on the perjury count.

On the basis of the letters from Stephenson and the other juror, Mulligan's lawyers filed a motion to set aside the verdict. Judge Owen then questioned Stephenson, who said her lawyer had adviser her that she could honestly say she hadn't even been involved in a criminal case, the felony assault charge having been dismissed. Her lawyer told the judge that he "certainly could have" given that advice.

The judge, concluding that Stephenson had performed in good faith as a juror, ruled that Mulligan had had a fair trial by an impartial jury, as required by the Constitution. He declined to set aside the verdict.

The 2nd U.S. Circuit Court of Appeals affirmed last April. Mulligan revew the ruling, alleging mainly that Stephenson's "bias, misconduct and incompetency" had deprived him of a fair trial.