Stanton was a corrupt police officer who was tasked to kill Dolores Abernathy.
Stanton, alongside another police officer, were hired through the Rico to assassinate Dolores Abernathy, who was being transported by an ambulance, which they stopped.
Caleb Nichols realised that the officers were corrupt and tasked to kill Dolores, and asked the EMT's in the Ambulance to contact a patrol-car, which led to Stanton and his colleague to kill the them all.
Stanton approached Dolores, prepares to shoot her, but Dolores awakes and uses a medical scalpel to kill him. She then kills his colleague, who was trying to kill Caleb, and stole their vehicle.
Stanton was stabbed by Dolores when he was trying to kill her in an ambulance.