Some will farm the work out to other labs. Most city departments will have a ride along program. You can ride with an officer or detective for a shift and find out what the job is really like. Just call your local department for more information. Local Agencies .
Every small town has a police force.
They will also have a detective or two, but those guys don't retire too often and competition is pretty severe. There will be a few support positions, but, obviously, the smaller the locality, the smaller the police budget, the smaller the police force. Private Sector . There are plenty of private agencies out there. Some are very good, very high profile and very well known.