The defense in the murder trial of Richard Lee Earman rested its case yesterday, after two days of testimony that sought to shred the credibility of the prosecution's main witnesses and to portray Earman as the innocent victim of circumstance and his own part criminal record.

Earman is charged with the murders of Arlington real estate salesman Alan Foreman and his fiancee Donna Shoemaker. They were found shot to death May 8 in Foreman's yellow Jaguar in the garage of his home at 1201 N. George Mason Drive.

Arlington Commonwealth's Attorney William S. Burroughs, who is prosecuting the case, has relied heavily on the testimony of two Arlington County jail inmates who testified that Earman told them he committed the murders. The prosecution's third main witness is Ray Moore Tugwell, a childhood friend of Earman who testifiedthat Earman offered him $5,000 to kill Foreman three months before the salyings.

Yesterday Josette Shawn, Earman's fiancee, testified that Tugwell called Earman seven times at her apartment and that because of a special device on her telephone she was able to hear both sides of the conversation. According to Shawn, Tugwell called only to ask Earman if it was safe for him to return from Canada, where he said he had gone to avoid testifying against a man indicted for murder.Tugwell, like Earman, was convicted in 1968 for his role in the "beltway burglars" gang that police say broke into more than 5,000 homes in the Washington area in 1966.

Defense attorneys yesterday also called Thomas E, Bailey, an Arlington County jail inmate who testified that Larry G. Piper, one of the inmates to whom Earman allegedly confessed, "never told the truth."

Bailey also said that he had warned Earman the day Earman entered the jail that Piper was "the jailhouse snitch" and that anything he said to Piper would be repeated to law enforcement authorities.

Bailey was only the last in a group of inmakes who said that neither Piper nor Ronnie James, the other inmate who said Earman confessed to him had reputations for honesty or credibility.

The defense also called a forensic psychiatrist to the stand to explain to the jury what an anti-social personality is. Tugwell was diagnosed as an anti-social personality in 1966.

According to Dr. Joseph Smith, a forensic psychiatrist at St. Elizabeths Hospital in the District, those afflicted with the personality disorder are often pathological liars and will take whatever course of action suits them without having feelings of guilt or conscience. Smith said that there was little chance that a person whose personality was diagnosed as antisocial in 1966 would have changed greatly in the last 1 years.