'I was almost a school shooter': Colorado dad pens open letter

Following the massacre of 17 students and teachers at a Florida high school last week, a Colorado father of four wrote an open letter Tuesday claiming that the only thing that stopped him from carrying out his own bloodbath 30 years ago was his inability to get a gun.

"I was almost a school shooter," Aaron Stark wrote in a letter shared with NBC affiliate KUSA. "I am not a school shooter because I didn't have access to guns. Guns don't kill people, people kill people. But people with guns kill lots of people."

Stark wrote that he felt like an outcast in 1996, when he attended Denver's North High School, where he was allegedly bullied and had a very chaotic childhood.

He told KUSA that he'd become enraged and harbored suicidal and homicidal feelings as a teen. He said he tried to buy a gun so he could kill his classmates and then himself.

"I was going to try and kill a lot of people and then kill myself," he said during an emotional interview. "It was not directed at the people, it was directed at myself."

"If I had rifle I would have been a killer but if I had love I wouldn't have wanted a rifles," he said, tearing up. "The only things that brought me out of it were true friendship."

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Stark said he overcame that phase of emotional instability and now has a loving family. He said he was motivated to write the letter after his wife and daughter "kept saying how they could not understand what could make someone do this."

"Sadly, I can," he wrote. This is a hard conversation to have, but we must have it."

Stark said later on MSNBC Tuesday afternoon that "we need to have a hard look at the effect that guns have" and said in the aftermath of the shooting people needed to be looking at both mental health and gun reform. He also called for people to show more compassion to others.

Amanda Nickerson, director of the Alberti Center for Bullying Abuse Prevention at the University at Buffalo Graduate School of Education, said the letter touched on two important themes in violence prevention: compassion and connectedness, as well as access to guns.

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"This is someone who can speak from a perspective of having been there and being able to reflect on what stopped him and what we can do further," she said.

"Clearly it seemed like reflecting back he was saying he didn't have that and we know that isolation and that lack of protective factors and connectedness makes a difference," she said.

"Another very important topic is that he didn't have access to guns and to these more high capacity machine guns as well," she added.

Nickerson said it was important to have these public conversations to take away some of the stigma around mental health and illness.

"It's important to know this isn't just a mental health issue, there're many people who suffer from mental illness that are not at all violent. The fact that he's hitting upon traumatic background, lack of connection and then his violent tendencies or access to firearms — I think those are really some of the key issues to be having in this conversation," she said.