Georgetown hairdresser Raymond Louis Urgo held a trembling hand over his eyes yesterday as his attorney asserted that Urgo did not intend to kill Elen Dana Kisacky last January when she was shot through the mouth at an Arlington party at which police say there was group sex and marijuana.

Urgo's trial, in which he is charged with murder and use of a weapon during the commission of a felony, began yesterday as defense and prosecuting attorneys began unraveling the bizarre events of a party at Urgo's Arlington Towers apartment Jan. 8.

When questioning prospective jurors, Richard Ben-Veniste, one of Urgo's two attorneys, said there may be evidence that Urgo, 32, and others "engaged in sexual activity that will probably differ from your own standards of conduct."

One woman asked to be excused because she said she could not impartially judge Urgo based on possible sexual evidence.

Ben Veniste also said evidence may be presented in which Urgo and others "may have taken marijuana" during the party. Two prosspective jurors asked to be excused, saying they had adverse feelings toward drugs.

Assistant Arlington Commonwealth's Attorney William A. Nunn III, presented his case in a brief opening argument.

"On Jan. 8 at approximately 9 p.m. (Urgo took a .357 magnum loaded five of six chambers, placed it in the victim's mouth, cocked it and pulled the trigger. And he intended to do just that," Nunn said.

Without detailing what occurred that night, Ben-Veniste said that on "the overwhelming bulk of evidence we will have no argument with the prosecution."

Miss Kisacky's death "was caused by an accident, a tragic terrible, senseless accident," Ben-Veniste said.

Urgo's key evidence will be a tape-recording of a telephone call Urgo made to Arlington police "immediately after the accident," Ben-Veniste said. "This tape recording will demonstrate to you with tragic eloquence what was going on in Raymond Urgo's mind right after the incident."

The first prosecution witness is expected to be called today.