When Melvin L. Turner, a veteran D.C. fireman, returned home from work on July 3, 1978, he sat down and told his wife a story even he couldn't believe: a 15-year-old girl had just accused him of raping her in the back of an ambulance as she was being driven to Capitol Hill Hospital for treatment of a knee injury.

His wife Denise recalled yesterday that she took her worried husband's hand and told him not to take the girl's charge seriously, that everything would work out.

But what followed was a year-long nightmare in which Turner was formally charged with rape and carnal knowledge of the girl, suspended without pay as a firefighter, his wife and children plagued with harassing phone calls, and his family forced to the edge of bankruptcy.

Yesterday, Turner, his life virtually ruined, was acquitted.

But that was small consolation to Turner, whose attorney presented witnesses who testified during the fourday D.C. Superior Court trial that no signs of sexual intercourse - forced or otherwise - were found when the girl was examined shortly after the alleged attack.

"We generally thought the government's case against Mr. Turner was ridiculous," said David A. Willis, foreman of the six-man, six-woman jury.

From the moment that Turner's name appeared in the newspapers as having been charged with rape, the Turner family's life was changed.

"We began receiving dozens of phone calls from people who said they wished my husband was sent to prison for life," said Denise Turner."One caller said my husband shouldn't be allowed on the street because he might rape small children."

The phone calls became so distressing that the Turners were forced to leave their suburban Maryland home for a week to escape them, Turner recalled.

That was only the beginning. The day after he was officially charged with rape, Turner said he was suspended without pay from his $16,000-a-year job as a firefighter and he was forced to scramble for another source of income.

He quickly took a job as a supermarket cashier, earning about half what he had as a firefighter to keep up the $378 monthly payment on his house and the $121 monthly car note.His wife, who had quit work earlier to care for their new baby, had to return to work to help balance the family budget.

But even so, the Turners were not able to earn enough to keep up with their bills. "By last December, we had decided to just let everything go unpaid except the essentials - food, clothing, the car and the house notes," Denise Turner said.

They attempted to fend off their creditors, several of whom took the Turners to court in an effort to force payment of their bills, with payments of $5 or $10 a month, "just to let them know that we intended to pay," she said.

Friendships suffered, too, the Turners said. Some friends read and believed newspaper accounts of the alleged rape. "One man who we believed was our friend called and asked why my husband would do such a thing," Denise Turner said.

On the playground, she said, school children taunted the couple's daughter, Maria, 9.

"We had tried to prepare our daughter for the comments we knew she would hear from her playmates," Turner said. "I explained to her what rape meant and told her that because her father had been accused of the crime didn't mean he did it. I told her that 'Daddy' had to prove he didn't do what they said."

But Maria cried more than once as other children called her father a "rapist" and laughed at her on the playground, Turner said.

Melvin Turner said the court system was a major source of frustration as he waited impatiently for his case to come to trial. He said there were five continuances of the case in 12 months. Each time he prepared to tell his version of the events of July 3 to a jury that he hoped would vindicate him. Each time he returned home with the charge of rape still hanging over his head.

At one point during the long wait, Barry Stiller, Turner's attorney, said the government offered to reduce charges against Turner if he would plead guilty to a lesser charge.

"I went to my client with the government's offer," Stiller said. "He said, 'Barry I would rather be convicted of the whole thing, than to plead guilty to something I didn't do.'"

As the jury deliberated yesterday, Melvin and Denise Turner sat quietly together. If the jury returned a verdict of guilty, their lives together would probably be over, they said. Turner could have received a prison term of from one year to life.

But after deliberating for an hour, the jury filed into the courtroom and announced the panel's decision to acquit Turner on both counts.

"Oh, God," Denise Turner cried out, bursting into tears of joy.

Assistant U.S. Attorney William O'Malley, who prosecuted the case, said that Turner's trial comes down to a question of who was to be believed. "I don't believe (the 15-year-old) would pretend to have a trick knee so that she could call an ambulance and arrange to ride to the hospital in it so that she could accuse a man of rape," O'Malley said. CAPTION: Picture, Denise and Melvin Turner, awaiting verdict outside D.C. Superior Court. By Vanessa R. Barnes - The Washington Post