A judge found a Waldorf teenager guilty of assault but cleared the youth of more serious charges in the random attack on a morning jogger who was beaten, stabbed and left bleeding near his Bryans Road home.

Charles County Circuit Court Judge Richard J. Clark delivered his verdict Wednesday afternoon after two days of testimony in the trial of Alexander Scott Teacher, who became the second person convicted in the Jan. 23 attack. Two others face trial.

Teacher's father expressed relief that his 16-year-old son was found not guilty of attempted murder, which carried a potential term of life imprisonment. Clark found prosecutors did not prove Teacher planned to kill the victim.

The judge "did exactly what he should have," said the youth's father, Walter Teacher.

The lead prosecutor in the case, Assistant State's Attorney Michael C. DiLorenzo, declined to comment on the verdict.

Clark set sentencing for July 29. He left intact the youth's $50,000 bond, but he said Teacher is to be placed under electronic monitoring in home detention.

The judge found Teacher guilty of two charges: assault and conspiracy to commit assault. Each carries a sentence of 25 to 50 years.

Teacher was among three teenagers who set upon Ronald Oliver, 60, after a night of drinking and aimless driving. A fourth youth charged in the attack remained in the pickup truck the group used that night. The youths wanted to attack somebody as part of what they called a gang initiation.

According to testimony, Teacher used a large folding buck knife to stab Oliver three times. The victim staggered the few dozen yards to his home and was taken to Civista Medical Center in La Plata, where he was treated and released.

A 13-year-old boy pleaded guilty to assault in the attack and is now in the custody of juvenile authorities. The Washington Post normally does not identify subjects of juvenile proceedings.

The 13-year-old testified that Teacher was a member of a gang called the Unseen Mob and that Teacher agreed to attack somebody as an initiation rite to gain entry into the Crips.

Sheriff's Lt. Michael Wyant, who monitors gangs for the sheriff's office, said no branch of the Crips, a nationally known gang, operates in Charles County.

Wyant said dozens of groups in Charles County call themselves gangs or use the roughly equivalent terms "mob" or "crew." Few of the groups have more than five members, Wyant said. He said none operates as a street gang that controls a defined area and traffics in drugs or guns.

Young people involved in the groups are drawn by a "mythical attachment to gang life," Wyant said. However, such youths sometimes inspire one another to commit crimes, he said.

"Unfortunately, sometimes these nascent groups are encouraged to cross that line," Wyant said. "The fever gets built up. . . . They've seen the movie [and think] this is what you're supposed to do."

Teacher's attorney, Franklin B. Olmsted, said he would seek to have the youth's case sent to juvenile court. Teacher was tried in adult court because of the seriousness of the attempted murder charge. With that charge voided, the reason to remove the youth from juvenile authorities had disappeared, Olmsted said.

DiLorenzo said prosecutors would oppose such a move because perpetrators committed under the juvenile system often spend less time incarcerated than those sent to adult prisons.

Two other youths accused in the attack face trials scheduled for July and August. They are Randy Rogers Jr., 17, of Indian Head, and Michael A. Hedges Jr., 16, of Bryans Road. They also were charged as adults.