The back seat of a police car is not comfortable. For one thing, it is made of hard plastic or smooth vinyl, so it can be easily cleaned (the back seats of cop cars end up covered in a surprising variety of human bodily fluids). In some cars, the seat is cramped, forcing suspects to sit very low or bend their heads down. To some extent, this is done to psychologically suppress people in the back seat, but it also makes it tougher to gain leverage or momentum if someone tries to launch an attack.
What protects police officers in the front seat from violent prisoners in the back seat? Some combination of a steel mesh cage and bulletproof glass is installed to keep them safe, along with steel plating behind the seats to prevent stabbings. The rear windows are reinforced with a wire mesh -- although they're not usually bulletproof. While strong, they can be kicked out by a forceful enough person [source: Hiltunen]. Needless to say, the rear doors of a police car cannot be unlocked from the inside.
In the trunk of a patrol car, officers store any bulky equipment they might need at a crime scene. This can include bulletproof vests or other body armor, a shotgun, first aid kit, a portable defibrillator, specialized tools (such as bolt cutters), or other gear specific to that officer's training and assignment.
There are a few other details unique to police vehicles, too. One is the run lock ignition. At a crime scene, the officer may want to leave the car running for an extended period of time so the lights and radio can stay on without draining the battery. Run lock allows the engine to run without the key being in the ignition. If someone tries to steal the car, the run lock system cuts the engine when the parking brake is disengaged [source: Emergency Vehicle Solutions].
The interior lights in a police car can switch from typical white lighting to red lighting. Red lights don't affect your night vision as much, so during a nighttime traffic stop an officer can use the red light to read a driver's license or other paperwork. Then when the officer leaves the car, he or she won't be suddenly blinded by darkness.
Up next, we'll take a look at the history of police cars.