Shaun O. Harrison reacts as attorneys give closing arguments during his jury trial in Boston. (Pat Greenhouse/The Boston Globe/AP)

He had been known fondly as “Rev,” a youth minister and dean at a Boston high school, who worked with gang members and helped lead anger management courses, a position that regularly brought him into contact with police officials.

But Shaun O. Harrison’s arrest in 2015 on charges that he shot a student jolted Boston’s public school system. And details about what prosecutors said was the 58-year-old’s secret life came out during his trial in connection with the shooting of a 17-year-old student.

Prosecutors said Harrison bragged to students about owning guns and told them he was connected to the Latin Kings gang and had killed someone before, according to the Boston Globe. Investigators found guns, ammunition, marijuana and a mural of the Latin Kings in a search of his apartment and storage unit.

On Thursday, Harrison was convicted of shooting a student, Luis Rodriguez, whom officials said Harrison had recruited to sell marijuana. The jury deliberated for about a day before convicting Harrison. They found him guilty of armed assault with intent to murder and other gun- and drug-related charges. He faces as many as 20 years in prison on the assault charge.

Harrison met Rodriguez at English High School, where he worked as dean of academies, a role that required him to help students with behavioral, social and emotional problems.

During their initial meeting in the cafeteria, Rodriguez testified, he told Harrison he was high on marijuana. He said Harrison told him he had smoked the drug the night before.

Police say Harrison later asked Rodriguez whether he wanted to make some money and promised him “girls and weed,” according to MassLive.

Harrison gave the teen marijuana to sell on at least three occasions, including one time in his school office, according to the Globe.

Prosecutors said Harrison attacked Rodriguez because of slumping drug sales.

On March 3, 2015, Rodriguez met Harrison at a gas station in Roxbury, and prosecutors said Harrison shot Rodriguez with a .380-caliber handgun.

The jury heard snippets of 911 calls made from the scene.

“He’s bleeding bad,” a witness said in one. “Kid came running out from an alley, bleeding, said, ‘I don’t want to die, please help me.’ ”

Rodriguez didn’t initially tell police who shot him, the Globe reported.

“It took me a while to get all my thoughts back together after being shot in the head,” Rodriguez testified. “I was in such denial. I knew who did it. Of course I knew who did it.”

Rodriguez suffered a broken jawbone, nerve damage and hearing loss. The bullet entered his head just beneath his right ear and narrowly missed his carotid artery, according to the Associated Press.

Harrison’s lawyer, Bruce Carroll, admitted that his client kept unlicensed guns but said he had inherited them from his parents. He disputed that Harrison shot Rodriguez, the Globe reported.

Carroll did not return a call requesting comment.

Harrison had maintained his innocence.

“I never lived a double life. I never, never, sold drugs. I never, never sold drugs; I never sold guns, never turned kids into gang members,” he told 7 News Boston from jail as he was awaiting trial in 2016. “Me? I would not even know how to do that.”

“This guy is probably the last person we would expect,” Police Commissioner William B. Evans said after the shooting in 2015. “He was an advocate for anti-violence. Why would he be on our radar screen?”

A report compiled by the school district’s Office of Labor Relations after the shooting detailed other allegations against Harrison. While working at another school in South Boston in 2012, Harrison was the subject of allegations that he pushed a female student in the back and threw a roll of tape at her. The pushing was not substantiated, the report said, but Harrison was counseled about his “unprofessional behavior” and issued a written warning.

Harrison also was the subject of allegations that he made inappropriate statements to two students and discussed recreational drug use. The headmaster found that Harrison had made the inappropriate remarks but that the allegations about the drug-use comments were not substantiated.

When he was hired at English High in January 2015, he beat out about 50 other applicants, the district report said. The day of the shooting, it was reported that Harrison had allegedly threatened to smack a female student and pushed her, for which the headmaster of the school decided to fire him two days later.

“Shaun Harrison went through the same hiring process as any other employee that is hired by the Boston Public Schools,” the report concluded. “In the case of Shaun Harrison, an investigation into each of the three disciplinary actions found each decision, under our existing policies, to be the correct and just course of action.”

The report recommended that an outside entity review the district’s disciplinary policies.

“This defendant presented himself as a man of faith dedicated to helping young people,” Daniel F. Conley, the district attorney of Suffolk County, said in a statement. “He betrayed the victim and he betrayed the community he claimed to serve. It was only by sheer luck that the victim survived this attempted execution to identify Harrison for what he is — a violent predator and a fraud.”

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