Private investigator services in Maine are governed by the 32 M.R.S. § 8101 et seq. (Maine Private Security Industry Act) and regulated by the Maine State Police — Special Investigations Unit. A state-level license is required to operate as a private investigator for compensation in Maine.
Quick Facts: Maine PI Licensing
| License required | Yes |
| Licensing authority | Maine State Police — Special Investigations Unit |
| Governing statute | 32 M.R.S. § 8101 et seq. (Maine Private Security Industry Act) |
| Official license lookup | https://www.maine.gov/dps/msp/specialty-units/special-investigations-unit |
| Authority website | https://www.maine.gov/dps/msp/specialty-units/special-investigations-unit |
| Last reviewed | 2026-05-17 |
Verifying a PI's License in Maine
Before retaining any private investigator in Maine, verify the individual’s license is active and in good standing. The Maine State Police — Special Investigations Unit maintains a public license search at https://www.maine.gov/dps/msp/specialty-units/special-investigations-unit. Search by the individual’s name or company name; the record will show the license number, status, and any disciplinary history on file.
What This Means for Hiring
Maine’s licensing requirement means the investigator you hire has, at minimum, completed the state’s training and background screening process. It does not guarantee competence on your specific case — surveillance, family-court, corporate, and skip-trace work each demand specialized experience. When evaluating a Maine PI, ask about case-type specialization, evidentiary chain-of-custody process, and prior testimony in the jurisdiction where your matter is pending.
Reference: All 50 States + DC
For licensing requirements in other jurisdictions, see the full PI licensing reference map.