Assuming this is in the USA, I want to note that there are many other available jobs in the protective services occupation, that can be public or private sector, that face the general public (or not), and that don’t have any particular positive or negative connotation attached to the job, even after hours.

The Bureau of Labor Statistics (BLS) has a fantastic reference for available occupations:

www.bls.gov/ooh/protective-service/home.htm