Wallace was an aspiring rapper with social media accounts filled with videos.
Guns are a central theme as he rhymes about shooting people, including police.
But his videos also include songs about social causes and police injustice.
RELATED: Philadelphia police on alert amid civil unrest following fatal police shooting of Walter Wallace
Court records show Wallace was currently awaiting trial for allegedly threatening to shoot a woman and her house up.
In 2017, he pled guilty to robbery, assault, and possessing an instrument of crime after kicking down the door of another woman and putting a gun to her head.
He was sentenced to 11-23 months behind bars.
And in 2013, he pled guilty to assault and resisting arrest after punching a police officer in the face.
Police Commissioner Danielle Outlaw said that it was unclear what officers who responded to yesterday's call knew about Wallace.
"There are several questions that need to be answered... including what the officers knew when they responded, what was put out by radio and how any previous contact with Mr. Wallace factored into yesterday," Outlaw said.
RELATED: Dozens of people arrested, 30 police officers injured as tensions erupt in West Philly following fatal police-involved shooting
The courts clearly had concerns about his mental health.
A judge ordered Wallace to undergo a psychiatric evaluation and treatment as far back as 2013.
His family says he was bipolar.
"I do know that he was on a regimen of lithium and that says to me he was under a doctor's care, and that says to me officers who are trained - invisible ink - properly should notice certain things when they arrive at the scene," said family attorney Shaka Johnson.
Meanwhile, dozens of officers were injured by rocks and bricks in clashes with protestors after the shooting.
Some neighbors have said those protestors were not from the neighborhood.
Commissioner Outlaw addressed those concerns.
"Speaking anecdotally - we tend not to like to speak anecdotally - but I will tell you the crowd that was out there on the scene, the residents from that neighborhood those, who witnessed the incident, those were the folks that I interacted with while there. Those were not the same people that we later interacted with once I left that scene. It was a completely different group, and quite frankly, demographics that we saw there and I heard from the community some of the same frustrations expressed as well," Outlaw said.