I would check with the local community colleges in the area. One here in the Denver area offers a part time and full time program which will give you the P.O.S.T. (Peace Office Standards and Training) certification. This is the minimum requirement for getting into the police academy which most departments require. Completing the Comm. College program here gives you approx. 30 credit hours towards an associates in criminal justice. Most departments want you to have at minimum a bachelors degree.
I am considering this myself. I already have an associates in art as well as a bachelors, so I don't know whether I want another associates or I would just get my Masters. Decisions, decisions, decisions.