John A. Rothrock Jr., the Fairfax County District Court judge whose pioneering decisions altered jurisprudence concerning the mentally ill, juvenile offenders and drunken drivers, is stepping down.

As his 25-year career on the bench comes to a close, Rothrock is contemplating a future in which his Rappahannock sheep farm plays a large part.

"I'm going to practice law here in Fairfax," Rothrock said in an interview last week.

"Maybe raise a little cain here and there," he added mischievously. "And there's always the farm.It's old and it always needs work."

Rothrock, 55, and his wife Nancy divide their time between their historic house in Fairfax, a short two blocks from the Fairfax County Courthouse, and their farm "up in the country."

They have two children, a son, John, who is a physician, and Sid, 14, who attends Wakefield, a private school in Rappanhannock County.

Although Rothrock officially retired in January, he is still at the court several days a week, cleaning out the accummulation of along legal career.

Rothrock said one of his proudest achievements was founding the Alcohol Safety Action Program, which is now standard throughout the state.

"ASAP was an idea that had been around for a while and the Department of Transportation definitely wanted it," he said. "It's a training course for drunk drivers lasting about six months. If the offender makes it through the course successfully, then the charge is reduced. The program has been very succssful."

The Fairfax County Council on Alcoholism honored Rothrock in 1972 with its achievement award for his introduction of ASAP.

Rothrock also views with pride his work on the court in cases concerning the mentally ill. His deicsion over the years helped change commitment and detention procedures for the mentally ill.

"I tried to humanize and moderinze the commitment procedures to protect the mentally ill as much as possible," he said.

While a firm believer in compassion as a tool to help people, Rothrock was quick to point out that his tenure included some hart-line stances.

"I was a pretty tough drug judge," he recalled. "You have to realize that 25 years ago people went to jail just for possession of marijuana. Then the law was changed to permit first offenders to be put on probation."

Rothrock is uncompromising in his resistance to legalization of marijuana.

"I'm all for giving first offender's a break, but after that it's something else. And I don't like to hear about police officials who take the attitude that they can't enforce drug laws so why brother to try," he said.

As he reminisced, Rothrock talked about the immene changes in Northern Virginia during his 25 years on the bench.

"I've seen this area grow and it's been interesting in that it hasn't been a stable area. It underwent many changes and the law had to change with it. It just becomes more and more complex.

"For instance, bond procedures have changed a great deal, particulary regarding the Miranda decision. I can't help but feel that Miranda has been overdone, that to dismiss or throw a case out of court because a defendant didn't have his rights read is somewhat acute."

Rothrock also expressed concern about the changing role of police in modern life.

"I've seen policemen change to public relations officers and I don't particularly like it," he said.

"I should also add there seems to be a growing hostility between people and the courts, partly because the people in this area don't simply accept legal procedures.

"We're fortunate in having a citizenry whose blood circulates above the neck. The situation is not necessaryily bad, but it certainly gets complex."

Seven full-time judges normally sit in the General District Court in Fairfax. They handle misdemeanors, traffic offenses, civil suits up to $5,000 and preliminary hearings on felony charges.

Until 1965, the judges also heard juvenile cases, but Rothrock initiated a change that led to the present system of juvenile court.

"It was necessary, not only to have a specialized court for juveniles but to reduce the District Court's tremendous caseload," Rothrock said.

Katy Ratiner, administrative assistant to Chief Judge Robert M. Hurst, said that Rothrock, who was chief judge until 1976, "will greatly be missed."

Joined by staff members Peggy Peck and Nancy Brown, each of whom worked with the judge for 23 years, Ratiner said, "He has always been so courteous and friendly and understanding.

"We have so much respect for him as a human being as well as a judge. He always took time to explain things and was respectful of people.

"All the staff have nothing but the best wishes for him. He really made a phenomenal difference in the court."

Rothrock, in turn, praised his staff "and all the other judges for making my time here so meaningful."

Rothrock's successor has not been named and a permanent replacement will have to be selected at the next meeting of the General Assembly. However, an interim appointment may be made, Rothrock said.