Are the police background investigators able to determine if you've been fired or not from a previous job? I know that normal background checks by law can't ask this question. Do police employment investigators get special exclusion from this law?
In California, yes. CA law forces past employers to provide all of your records to a police background investigator and that the department seeking the info will repay the past employer for costs incurred making copies etc. If you even lied or fibbed on past apps, be prepared to explain yourself as a background investigator will most likely see it.