The distraught father who is charged with stabbing a boy he believed was a witness to a sexual assault on his daughter may have attacked the wrong person.

The boy's attorney said Tuesday the 17-year-old Houston-area high school junior did not attend a weekend party where the sexual assault allegedly took place. Instead, the boy — whom he described as a computer "techie" — spent the weekend with his parents.

"He was not at any party at all," attorney Fernando Valdes said. "This kid was student of the month last month. He's not some thug that runs around gang banging. He hangs around computer guys. He's a techie, a good guy getting a bad rap."

Harris County Sheriff's Sgt. Kenneth O. Thomas said investigators don't know yet if the boy was at the party.

The boy, who remained hospitalized in good condition on Tuesday, was stabbed three times Monday morning by the father of the 17-year-old girl. The girl and her parents went to Wunsche High School in Spring to report the sexual assault to school administrators.

Around 8:30 a.m. Monday, the father spotted the boy in the school lobby, called out to him, then lunged at him from behind, Valdes said. The man stabbed the boy in the chest, before the teenager tried to wrestle the knife away.

The boy was stabbed again in the hand, then fell to the ground where the father stabbed him in the abdomen. The teenager knocked the knife out of his attacker's hand before school police managed to subdue the man.

Spring Independent School District police arrested the girl's father and charged him with aggravated assault with a deadly weapon. Court records did not indicate whether he had an attorney, and a telephone number listed for his address had been disconnected.

The Associated Press is not naming the man because his daughter may have been a juvenile victim of sexual assault and could be identified through the father's name.

Court records show that the 44-year-old man had received deferred adjudication for discharging a firearm in 2001, and pled guilty to theft in 1990.

"This was an unwarranted act of vigilantism," said Valdes, who said that the boy knows the girl, but had never before seen her father.

The girl told her parents that she had been assaulted at a party late Friday night or early Saturday morning, according to the sheriff's office, which is still investigating the sexual assault.

The girl's parents thought she was sleeping in a backyard tent with her younger brother Friday night, but discovered after midnight that she was no longer there, Thomas said.

After calls to her cell phone were not answered, the parents reported her missing. The girl returned home around between 2:15 and 2:30 a.m.

She then admitted that she had snuck out around 12:45 a.m. to go to the party, attended by seven or eight other teens, Thomas said.