But long before the attack, court records show Harper had been arrested dozens of times.
In addition to the most recent robbery charge, Denver police arrested Harper in 2011 for attempted murder.
According to a probable cause statement in the case, during an argument with the victim who Harper had two children with, "The suspect used his fist to repeatedly hit the victim about her body," court records show. "He then grabbed the two-year-old child, ran down the street, and threw him into the ground."
When a good Samaritan tried to stop him, Harper allegedly "grabbed a handgun" and then "fired approximately five rounds at the good Samaritan," the statement further states.
A plea deal was reached in the case, and Harper pleaded guilty to a lesser charge of possession of a weapon by a previous offender and was sentenced to two years of probation.
Ken Lane, a spokesman for the Denver District Attorney's Office, said over sive years and more than 33,000 felony cases filed later, they don't have specific details about why a plea deal was reached in the case. Lane also said the lead prosecutor in the case is long gone, and therefore unable to provide additional context.
In 2013, Aurora police arrested Harper, who went by the street name “Blackoutt,” for opening fire on an ex-girlfriend and assaulting an officer.
Court records show Harper told police he only fired two shots at his ex-girlfriend because the revolver he had in the car at the time only had two rounds of ammunition.
Police stated in the affidavit that Harper was a known gang member, and on Facebook he is seen in photos flashing what appear to be gang signs.