A Virginia judge declined yesterday to name a special prosecutor for the trial of Joseph N. Martin, a former Northern Virginia insurance salesman accused of hiring a man to kill an Arlington couple in 1977.

Arlington Circuit Court Judge Charles S. Russell's decision came after he was assured that prosecutor William S. Burroughs would not be a major witness in the case against Martin.

"If (Burroughs) is going to testify to any matter . . of substance then, in my view, he cannot prosecute, nor can any member of the Commonwealth Attorney's staff," Russell said. "It's an intolerable burden on the defendant to be prosecuted by someone who is a major witness against him."

The issue of whether a special prosecutor was needed had been raised in earlier proceedings on the case, but Martin's attorney, Gerald Treanor, told Russell yesterday that without knowing what Burroughs' testimony would be, he could neither oppose nor support a motion for a special prosecutor.

After repeated assurances by Helen Fahey, an assistant prosecutor, that Burroughs would not "be a major witness," Russell decided against the appointment of a special prosecutor and set Oct. 15 as the date for the trial. Lawyers say they expect the trial will last at least three weeks.

The celebrated case against Martin dates back to 1977, when Martin and Richard Lee Earman were indicted on charges of murdering Alan Foreman and Donna Shoemaker.

Earmen was acquitted of murder charges after an eight-day trial during which Burroughs abruptly dropped charges against Martin. Last spring Martin was indicted again on murder charges after Earman testified that Martin had hired him to kill the couple in order to collect on a $56,000 life insurance policy.

Martin, 28, a Las Vegas resident who is free on $50,000 bond, did not attend yesterday's hearing. He has pleaded innocent to charges that he hired Earman, who has pleaded guilty to murder conspiracy charges.

Last year, Arlington detectives and others complained to state officials that Burroughs refused to seek an indictment against Martin despite evidence which they said indicated his involvement. Virginia Attorney General J. Marshall Coleman subsequently ordered a probe of Burroughs which Coleman said, cleared the prosecutor of criminal misconduct charges.

Burroughs is running against Henry E. Hudson, his former chief assistant, for election to a second four-year term in the Nov. 6 elections. Burroughs' handling of the murder case is expected to be a major issue in the election.