An Arlington judge yesterday ordered Joseph N. Martin, 28, a former Northern Virginia insurance salesman, bound over to a grand jury on a charge that he conspired with Richard Lee Earman to murder a young Arlington couple in 1977.

Martin appeared briefly yesterday before General Distrcti Court Judge Richard W. Corman, who agreed that Martin be allowed to return to Las Vegas home on a $2,500 bond. An Arlington grand jury will decide April 16 whether to indict Martin in connection with the execution-style slayings of Alan Foreman, 26, and his finance, Donna Shoemaker, 25.

Martin has pleaded innocent to a charge that he hired the 36-year-old Earman, a former real estate agent, to kill Foreman in order to collect on a $56,000 insurance policy that Martin had sold Foreman.

In dramatic testimony Tuesday, Earman calmly recounted how he and Martin plotted to kill Foreman. Acquitted in 1977 of murder charges, Earman testified that he killed the couple and his role in the shootings "didn't bother" him.

In 1977 Martin was arrested with Earman on murder charges, but during Earman's trial prosecutor Williams S. Burroughs abruptly dropped charges against him. Last month Martin was arrested on a murder conspiracy charge.

Earman, who has said that he has lied to police and others about the case, is scheduled to be sentenced July 27 on a conspiracy charge which carries a maximum sentence of 10 years in prison. Because of the constitutional protection against double jeopardy, Earman cannot be tried again on charges of murdering the couple.