A criminal complaint alleges that Shelby’s "fear resulted in her unreasonable actions which led her to shooting" Crutcher "unlawfully and unnecessarily."
Shelby shot Crutcher as he attempted to reach inside his vehicle, after allegedly not complying with her commands. His family has argued that there was blood splattered on the window, indicating that it was up at the time that he was shot.
An affidavit signed by an investigator states that Shelby became highly emotional, and shot Crutcher, despite not seeing a weapon or any indication that a weapon was present. The affidavit accuses the officer of "escalating the situation from a confrontation."
Shelby "is very, very distraught about… the fact that she has taken a human life. She said the other day in her interview with homicide detectives, 'I was never so scared in my life as in that moment right then,'" her attorney, Scott Wood, told ABC News prior to her arrest.
Despite the charges, Shelby has not been fired from the department. Initially, she was placed on paid administrative leave, but it has been changed to unpaid leave following her arrest. The department will conduct an internal-affairs review and make a decision regarding the future of her employment on the force following a verdict.
"Officer Shelby, although now charged, is presumed to be innocent under the law until a judge or jury determines otherwise," the Tulsa County District Attorney's Office told ABC News.
Shelby is scheduled to appear in court for the first time on September 30. If she is found guilty, the charge carries a minimum prison sentence of four years.