Christian Hall, 19, was shot three times by the Pennsylvania State Police, and his parents are demanding an independent investigation

christian hall and family
Credit: Courtesy Hall Family

Isolation during the pandemic had been difficult for 19-year-old Christian Hall, who was also navigating his first heartbreak.

"He couldn't hang out with his friends. We couldn't visit our families," says his mother Fe Hall. "So he felt, I think, disconnected. So that contributed to his depression."

Despite his emotional struggles, Christian continued to work at the local grocery store in Stroudsburg, Pa. At 6 a.m. on Dec. 30, Fe drove her son to work. After she dropped him off, the details of Christian's day get murky. The only thing they know for sure is that he clocked out an hour later.

Everything else they learned from a viral video from a bystander: Christian standing on a highway overpass, a pellet gun in his hand and an hours-long confrontation with police. In the end, he was shot three times and taken to a local hospital, where he was pronounced dead.

At a press conference in March, Monroe County's Assistant District Attorney called the incident a "classic suicide by cop scenario," according to the Pocono Record, and said the use of deadly force was justified.

But the family's attorney, Devon Jacob, says the bystander's video shows Christian with his hands up.

"It was probably the least threatening position that the device could have been in," Jacob says. "But then they proceed to shoot him because he doesn't put the gun down. They just proceed to shoot him."

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Christian's parents are continuing to search for answers, which they say have not been provided. Instead of the county ruling on the incident, they want an independent investigation.

"We're looking for transparency because we were not afforded that. We don't think changes, police reform will come if there's no accountability," Christian's father, Gareth Hall, says. "Mental health reform. We believe if there had been a mental health professional there, then maybe [Christian] would not have lost his life."

It has been less than a year since their son was killed by police, and Fe and Gareth remain in the depths of their grief.

Gareth says it's difficult to drive past the overpass where he was shot without thinking, "My son was here," he says.

Fe says the holidays -- Mother's Day and Father's Day, most recently -- are unbearable.

"These are the things that we used to look forward to and now it's like, 'What are we going to do?'" she says. "I wake up in the morning and my first thought is 'Oh my God, he's not here.' What do I do?"

For more information about Christian Hall and other cases of deadly use of force, pick up this week's issue of PEOPLE on newsstands Friday.