Marshall's fight for social justice began in 2016 and has continued ever since, as he has had conversations with the Denver Police Department as they prepared changes to their use-of-force policy in the past two years.

"Through my activism, at first I was trying to create awareness," Marshall says. "But my main thing was to create change and to start the conversation and wake people up and open people's eyes to certain issues that's going on in our world today, to a lot of social injustices that go even deeper than racism. [My goal was] definitely to open people's eyes and hopefully create change and hope to really create a society that respects equality and promotes equality."

Marshall has also taken part in a police-training simulator that put Marshall in the middle of situations officers face in the line of duty.

"I feel like I had to go and talk to the police and work with them and go on ride-alongs, do simulators and have conversations," Marshall says. "That was part of the whole reason I did it. I didn't want to just do it and seem like I was against them. I wanted to take a knee, protest, but still work with them in hopes to maybe change something."

Naturally, there was pushback. Some of it, like tweets he received, were easy to forget. But one letter he received at UCHealth Training Center was much more concerning.

"It was a death threat, a letter that called me all kinds of racial terms and derogatory terms, saying that this is going to leave me in a wheelchair, threats and stuff like that," Marshall says. "So I definitely did receive some persecution on it. It was tough. Then somebody came outside and burned a shirt of mine or a shirt that had my name on it, outside the facility. It was a few things that I had experienced. I was able to just keep pushing through."