A Burke teenager who fatally shot a man outside a house party in Springfield in March pleaded guilty yesterday in Fairfax County Circuit Court to involuntary manslaughter and a felony weapons charge.

The parents of Brendan A. Tash, 20, still reeling from their son's death, had mixed emotions about Durrell M. Pretty's plea. They were pleased that the shooter was caught and convicted but dismayed that he will face a maximum of 15 years in prison at his sentencing in October.

"There was nothing involuntary about this," said Steve Tash, Brendan's father. "Basically, this guy got away with murder."

Pretty, 19, had been facing a murder charge and a more serious weapons charge. But yesterday, Assistant Commonwealth's Attorney John R. Murphy agreed to reduce both charges in exchange for a guilty plea.

Testimony at Pretty's preliminary hearing in May had been confusing and conflicting -- "that was a fiasco," Steve Tash said -- and a trial presented the possibility of an acquittal. "It would have been possible that this guy would have gotten off," Tash said.

So the family agreed not to press for a trial. "The positive side is that it does get us closure faster," Tash said.

Brendan Tash had walked through back yards in his neighborhood to the party in the 6200 block of Cardinal Brook Court, where a friend was celebrating his 21st birthday. Steve Tash said his son arrived at the party about 1:50 a.m.

About 30 minutes later, while Brendan Tash was inside the house, a confrontation erupted outside between partygoers and a group of about eight uninvited people. Initially, the uninvited people were asked to quiet down, then were told to leave. Detective Steve Shillingford testified that the uninvited people, including Pretty, chased the partygoers back into the house.

But the partygoers reemerged with baseball bats, Shillingford said, and chased Pretty and his group back toward their cars. As a crowd of 15 to 30 people surrounded Pretty and his friends, Shillingford said, a friend handed Pretty a .38-caliber handgun that he fired twice in the air.

The partygoers scrambled back toward the house. But Pretty then lowered the gun and fired another shot toward the crowd, Shillingford said. Brendan Tash was 50 to 65 feet away with his back turned, and the bullet struck him in the neck, Shillingford said. Tash had emerged only at the end of the confrontation, Shillingford said, and had never gotten near Pretty or the heart of the conflict.

Pretty, of the 5900 block of Queenston Street, was arrested three days later while working at Wegman's grocery in Fairfax.

"Brendan was a pure innocent bystander," his father said. "He died coming out, essentially, in defense of his friends. He was an honorable person. He was brave, and he was courageous. He was loved by everyone."

Brendan Tash had just gotten a job working construction, his father said. "He had a lot of potential," Steve Tash said.