A former psychiatric counselor at St. Elizabeths Hospital, accused in a murder-for-hire arrangement, was convicted by a Prince George's County jury yesterday of conspiracy to murder, attempted murder and several firearms charges.

Terry Tyrone Brown, 28, who prosecutors said had agreed to kill a Greenbelt insurance salesman in return for $2,000 from the victim's wife, could receive two life terms when he is sentenced June 14.

The victim, Phillip Andrews, was shot once through the shoulder on Jan. 20, 1982, and was fired upon again on Jan. 28, the day after he was released from the hospital. His wife, Leslie Boyd Andrews, was sentenced earlier this year to eight years in jail for her part in the alleged conspiracy.

Both prosecuting and defense attorneys, as well as several witnesses, described Brown as an intelligent, well-educated and ambitious counselor who had moonlighted as the financial officer for two local nightclubs and modeled on the side. Brown told the jurors that he earned about $36,000 a year and had never before been in trouble with the law.

But county police said that when they removed Brown, described by his attorneys as "a pussycat," from his MG sports car in the parking lot of Garfinkel's in Landover last year, they found a loaded .357 Magnum under the jacket of his three-piece suit, a butcher knife under the seat, and spent shells on the floor.

A loaded Derringer pistol was in his briefcase, along with more than 50 rounds of ammunition and what prosecutors said were the scrawled outlines of a conspiracy to murder.

Brown, who denied any involvement in the attempted murder, testified in court that the notes in his briefcase, which described Phillip Andrews' appearance, address, car, work habits, hospital room number and included his photograph, were jottings made while he was discussing with Andrews' wife the possibility of having her husband committed.

Brown said that he gave some of this information to police after Leslie Andrews told him that her husband abused her and had threatened to cause trouble at one of the nightclubs where Brown worked. He said that he carried guns because he regularly carried large sums of money from the nightclubs to the bank.

Brown was lured from his home on Capitol Hill to Landover by county police hours after the second attempt on Phillip Andrews' life. After arresting Leslie Andrews on a tip from her father, they had her call Brown and arrange to call off the arrangement and pay him $1,000 at Landover Mall.

Defense attorney Victor Houlon produced two women as alibi witnesses. Both women claimed to have been at Brown's home when the shootings occurred.

But prosecutor David Simpson countered with the testimony of a third woman who said that she had spent the night alone with Brown before the second shooting, when Brown said he had been working, and had seen him drive away from the house shortly before the time a shot was fired at Phillip Andrews.

Circuit Judge Audrey E. Melbourne ordered that Brown, who has been free on bond and working as a computer analyst for the city government of Jacksonville, Fla., be jailed until he is sentenced.