McInerney, a student of Ventura County middle school stunned the students and school staffs with such a brutal act in his youth. If convicted, he faces up to life in prison.
Gay-rights advocates raised questions on Larry's death on how the school officials hadn't done more to stop the harassment toward Larry by students, including McInerney.
The conflict between the two boys, who both had troubled upbringings, didn't seem out-of-place for teens coping with adolescence. There were taunts, teasing and on at least one occasion, a scuffle between Larry and McInerney, who purportedly tried to get others to beat up Larry.
The day before the shooting, one of McInerney's friends told authorities that Larry uttered the words "I love you" as he passed McInerney in a hallway, according to court documents filed by prosecutors.
The friend said, McInerney told him he was "going to get a gun and shoot (Larry)," according to court papers. One of Larry's friends claimed McInerney told her, "Say goodbye to your friend Larry, because you're never going to see him again."
McInerney "then stood up as Larry collapsed to the floor, looked around at his astonished classmates and delivered a second coup-de-grace shot into the back of Larry's head," prosecutor Maeve Fox wrote in court documents.
McInerney has pleaded not guilty to murder, lying in wait and a hate crime. Defense lawyer Scott Wippert has not returned calls and e-mails seeking comment. Wippert, however, told the Ventura County Star, that Larry sexually harassed McInerney and the shooting was committed in the heat of the moment.
Larry, who told some people he was gay, lived at a center for abused and neglected children in the months before his death. Girls used him as a pawn to clear a table of boys at lunch, according to prosecutors. When Larry asked to sit with them, the boys got up and sometimes called him derogatory names.
McInerney came from an abusive household where his father, William McInerney, was sentenced for battery against his mother in 2000. William McInerney also was accused of shooting her in the elbow several months before his son was born.
He died in March 2009 of blunt-force head trauma at his home. The coroner ruled his death was accidental.
While McInerney will be tried as an adult because of the gravity of the alleged crime, some legal experts said the panel could be more lenient because of his youth.
"One, they recognize the younger you are, the more likely you are to be rehabilitated," said Tom Lyon, a professor of law and psychology at the University of Southern California. "And two, they see more impulsiveness in their actions."