A Fauquier County Circuit Court jury tonight convicted Warren Wesley Essex of second-degree murder and drunk driving for his role in a head-on collision last fall that left three people dead.

The murder verdict, sought by prosecutors in a crackdown on drunk driving, was believed to be the first such conviction of a driver in the state in an alcohol-related traffic case.

Second-degree murder carries a sentence ranging from five to 20 years, while manslaughter, a charge most often brought in fatal accidents resulting from drunk driving, is punishable in Virginia by one to five years and a $1,000 fine.

The 12 jurors, looking drawn and tired after six hours of deliberation, set sentencing for Essex at the minimum five-year prison term on each of three murder counts. It also recommended the minimum six months incarceration on the driving while intoxicated charge, for a total 15 1/2 year sentence.

Judge William Shore Robertson, who will hear post-trial defense motions in the case later, is empowered under state law to reduce the jury's recommendation or order that the prison terms run concurrently.

Essex, a 25-year-old construction laborer who had been free on bond, was placed in the custody of sheriff's deputies following the verdict.

Despite a request by Robertson for silence in his courtroom, several friends of Essex gasped and then sobbed as the jury's decision was read. The parents of two teen-age girls killed in the crash sat impassively among the spectators.

The victims were James E. Carter, 25, a passenger in Essex's car, and Nora Lynn Neale, 17, and Deborah Lynn Gouldthorp, 16, who were returning home from a Culpeper bowling alley in a small pickup truck driven by Gouldthorp's brother when the collision occurred about 10 miles south of Warrenton.

"I hope [the verdict] makes the most sweeping of changes" among drivers who drink, Neale's mother, Donna, said outside the courtroom. "I hope everyone in the state who drives hears about it."

Neale, head of a local chapter of Mothers Against Drunk Driving, an organization that favors tougher penalties in alcohol-related traffic cases, clutched a large color photograph of her deceased daughter, as she had throughout the trial.

Essex's two court-appointed lawyers said tonight they had made no decision on a possible appeal. If appealed and upheld by the state Supreme Court, tonight's verdict would have significant impact on the prosecution of alleged drunk drivers who kill others on Virginia's highways, said attorneys on both sides.

The verdict capped three days of argument over alcohol-related statutes in the state, which has no vehicular homicide law. The Virginia Supreme Court has never ruled that vehicles constitute deadly weapons, or that drunk driving is, of itself, a malicious act, two key elements of the prosecution case.

Judge Robertson, who denied a defense request that he dismiss the murder counts at midtrial, termed the murder issue "troubling." He had "the luxury," he said, of sending the question to the jury.

Under Robertson's instructions, the jury could convict Essex of murder only if it was convinced he acted with malice. The jurors could infer malice, they were told, if they believed the car was a deadly weapon, likely to cause death or injury, with Essex at the wheel.

"It was a grievous accident, but an accident nonetheless," defense lawyer Lee Albrecht argued today in his closing statement to the jury. Albrecht attacked the government's case as circumstantial and an attempt to make new law.

"Cars don't kill people. People kill people," countered assistant Fauquier prosecutor Roger Inger.