A divided Virginia Supreme Court upheld yesterday the 1984 murder conviction of a 27-year-old man serving four life terms for stabbing to death and robbing a wealthy Alexandria businesswoman and her longtime associate.

In a 4-to-3 decision, the court ruled that Alexandria Commonwealth's Attorney John Kloch's late disclosure during George Alec Robinson's trial that a key prosecution witness had failed a polygraph test had not prejudiced the case.

" . . . There is not reasonable probability that an earlier disclosure would have resulted in a different outcome," Judge John C. Thomas wrote in the majority opinion.

Robinson was convicted of killing Elizabeth Elliott, 68, and Karl von Lewinski, 71, with a 12-inch pair of scissors on July 9, 1984. He was sentenced to four life terms after the jury rejected the death penalty in the case.

In a sharply worded conflicting opinion, the three dissenting judges said they believed Robinson should be granted a new trial because exculpatory information, including the possibility that the key witness may have been involved in the crime, was withheld from defense attorneys.

"The commonwealth knew from the outset that if anyone else was placed at the scene at the time of the murders, the chance of convicting the defendant of the capital murders would be subverted substantially," Judge A. Christian Compton wrote for the minority.

Only the actual killer can be convicted of capital murder in the commission of robbery, according to Virginia law. The prosecution tried to show during the trial that Robinson acted alone in the killing, while the defense had argued that others were there.

Compton said defense attorneys were given no opportunity to investigate if prosecution witness Charles Ball was involved in the slayings. Ball had failed a police polygraph test when asked how he had found a pillowcase containing Elliott's personal belongings and had "intimate knowledge of the victims' backgrounds," Compton said.

Ball, whose whereabouts is unknown, lied about where he found the stolen items, "was familiar with the interior of the premises where the killings occurred, and had an extended history of being a violent person," Compton wrote.

George F. West Jr., one of the Robinson's defense attorneys, declined to comment on the decision yesterday. Kloch was out of town and could not be reached for comment.