Rev's beheaded body shows him wearing a gray long-sleeved thermal shirt when he was wearing a white thermal crew neck prior to being beheaded by Pulpo.
Voight makes a significant tactical error after the shots are fired, albeit a common one TV cops make. In a shots fired situation, officers such as the ones in the patrol car would be deployed to the rear of the building to prevent the escape of the occupant(s). Instead, all of the officers congregate at the front of the building. A similar error is made later on at the apartment building, which results in a vehicle pursuit.
Wilhite made a significant tactical error by standing on front of the door. Police are taught to stand to one side to avoid gunfire through the door.