There is no difference between the two other than the terminology used.

You can get books at a library or use the internet to investigate the skills that are helpful and required to be a competent private investigator.

Private investigators are private citizens and their powers are the same as the state laws are for a private citizen where they are in business.

In short a PI is not a policeman and they don't have the powers as police do. A PI can make a "citizens arrest" in California. In that case the PI would "detain" for the police to take custody.

In IL contact the licensing agency IDFPR for their requirements.

www.socalinvestigate.com

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