Webster's New World Collegiate Dictionary defines "motor pool" as "a group of motor vehicles kept, as at a military installation, for use as needed by personnel." But a police motor pool and its personnel are responsible for much more than that.
A police motor pool is not only a place to store vehicles. Most motor pools are also busy maintenance and repair facilities. In some larger departments, such as the Los Angeles Police Department, motor pool personnel also perform vehicle modifications, safety inspections and emissions testing, inspections on both Department and privately owned vehicles involved in traffic collisions, and "testify as subject matter experts for the City Attorney in auto fraud cases or in litigation of civil liability cases," according to the LAPD website.
Types of vehicles that may be kept at a police motor pool include, but are not limited to, standard patrol automobiles, unmarked and undercover vehicles, motorcycles, prisoner transport vehicles, off-road vehicles such as 4x4 SUVs, buses, special response transport vehicles for SWAT teams, armored personnel transport vehicles, mobile command center tractor/trailers, snowmobiles and even Segways.
Many police and sheriff's departments allow their officers and deputies to take their patrol vehicles home when they are off duty. This allows the motor pool facility's storage yard to be smaller, but doesn't diminish the need for adequate repair and maintenance facilities. Some smaller police agencies, however, outsource their maintenance and repair work to private garages.