Teen Killed By Homeowner Had A Record

The 15-year-old Mountlake Terrace youth who was shot and killed by an Innis Arden resident yesterday while apparently trying to break into the man's home was no stranger to law-enforcement officers.

Mountlake Terrace police Cmdr. Larry Ankrum said his department had numerous contacts over the years with the youth, Adam Costin.

According to police, Costin and two other youths were convicted last year of second-degree assault after beating a Seattle man with a baseball bat. The early-morning incident occurred in October 1992 in Mountlake Terrace. The fight started when the man emerged from a home and asked the youths to keep their noise down. The man, who was armed with a boat oar, suffered a severe head injury during the attack.

"It was an injury that could well have resulted in death," said Ankrum. "It was a particularly violent and brutal attack."

Costin and the two other youths were convicted in Snohomish County Juvenile Court. One of those other teenagers, who is 18, was involved in yesterday's incident and was in satisfactory condition at Harborview Medical Center with a gunshot in the groin.

County police warned Gene Maddox, the man who shot Costin, that he might be the target of gang revenge because Costin was associated with a local gang. Dave Robinson, county police spokesman, said he does not know which gang.

The wounded youth has been cooperating with police, Robinson said. The wounded teen, the suspect who escaped, and Costin are now being investigated as suspects in a series of home break-ins on Mercer Island, in Lake Forest Park and the Shoreline area. In several of those, elderly residents were overpowered and bound while their homes were looted.

Ankrum said police had responded to a number of disturbance calls over the years at the small home where Costin lived.

Neighbors last night described the residence as a noisy hangout for teenagers, with kids coming and going at all hours.

"They're out there partying, racing up and down the streets," said David Tomasi, who lives next door to the youth's family. "I basically just try to stay away (from home) as much as possible. . . . We're moving in May. We've just had enough of them."

Family members and friends gathered at the Costin home last night but declined to talk to a reporter.

Maddox, 41, was questioned by police then released last night.

According to state law, killing another person is justifiable when someone, such as a homeowner, is defending himself or others and believes the assailant is about to commit a felony or do great personal injury to the homeowner or someone at the location.

Costin was found in berry bushes at the rear of Maddox's home and had been shot in the back, police said.

A third suspect, 25, whose identity police learned yesterday, remained at large.

The shooting rattled some residents of the Innis Arden community already on edge after two home robberies in their neighborhood in the past six weeks.

Shirley Olsen, an Innis Arden resident, said she went as far as getting a gun permit some time ago but then "chickened out."

But yesterday Olsen vowed, "I'm going to get one."

Police said one of the recent Innis Arden robberies had been solved, and none of the three suspects was believed to be involved in the other.

Yesterday's incident started about 8:20 a.m. when the sound of breaking glass woke Maddox. He confronted the three suspects in the hallway, according to Maj. Jackson Beard. There was some shouting and words exchanged, and Beard said Maddox went to his bedroom and got a 9mm semiautomatic handgun. Beard said Maddox fired several times inside the home and apparently fired some shots at the suspects outside the home because detectives found bullet casings on a patio.

A baseball bat and a knife were found "in places they would not ordinarily be" inside the house, but it was uncertain whether they were weapons brought by the suspects.

Seattle Times staff reporter Dee Norton contributed to this report.