Totally changes the story! He “obtained” a firearm during the struggle... failure to secure a weapon while marching a suspect into the police station.
The procedure at our county Sheriff’s dept is pretty secure.
The officer arrives with a prisoner in the car and has to ask for a garage door to be opened. (they call it an intake bay) The officer then gets out of his car and secures his weapon in a gun safe. Then another officer enters the bay and assists in removing the prisoner from the car if needed and then all three are buzzed in.
One neat little trick is to have the gun safe wired with the intake bay garage door. If the door is open it closes when the officer turns the key in the gun safe.