According to the Maine Bureau of Motor Vehicles (BMV), ME requires all motor vehicles to undergo a safety inspection once a year. Vehicles registered in Cumberland County are also required to undergo an emissions test. You can get a safety inspection at many local mechanics and auto repair shops that are licensed by the state to conduct safety inspections. Inspections are regulated by the Maine State Police.
You have thirty (30) days from the time you become a Maine resident to renew your license and registration. If you have an out-of-state inspection sticker, you do not need to get your car inspected in Maine until your current sticker expires. If you do not have an inspection sticker, you must get your vehicle inspected immediately.
Since this last bit of information does not apply to your son's situation we contacted the Maine State Police since they regulate Maine's inspection process to clear up the 30 day rule and see what steps your son should have taken to get his inspection renewed since he was out of state in Massachusetts when the inspection sticker expired.
The ME State Police Motor Vehicle Inspection Unit responded that there is a 30 day 'grace period' as it pertains to expired inspection stickers in Maine within the first 30 days of expiration, not within the first 30 days of returning to the state. Your son could have requested and likely received a permit to operate his vehicle with an expired inspection to get to an inspection station in Maine. This is referenced in Title 29-A - Maine Motor Vehicle Statues. This portion of ME law (29-A 1759 Temporary permits and warnings) states:
1. Issuance - A law enforcement officer, an employee of a municipal police department designated by the chief, an employee of a sheriff's department designated by the sheriff, an employee of the Department of Public Safety designated by the Chief of the State Police or an employee of the Bureau of Motor Vehicles designated by the Secretary of State may issue a permit allowing operation of an uninspected vehicle to an inspection station for inspection.
2. Reconstructable vehicle. This section does not apply to reconstructable motor vehicles as defined in Title 10, section 1471.
3. Warning - The owner or operator of a vehicle operated with an expired inspection sticker during the first month immediately after expiration may not be issued a summons to court but may only be issued a warning. This warning must state that the vehicle must be inspected within 2 business days. Failure to comply with a warning is a violation punishable in accordance with section 1768.
Subsection 7 of Section 1768 of ME law notes that an owner or operator of a vehicle required to be inspected commits a traffic infraction if that person operates that vehicle or permits that vehicle to be operated without displaying a current and valid certificate of inspection or producing the certificate on demand of a police officer.
The Maine State Police told us that the State does in fact accept inspections from other states, for one year from the date of issuance. This can also be referenced in Title 29-A. Section 29-A 1752 of Maine Statues is titled Motor vehicles exempt from inspection and state that the following are exempt from inspection:
The first subsections lists cars registered in another state. A motor vehicle owned and registered in another state and displaying a valid certificate of inspection from another state or a federally approved commercial vehicle inspection program is accepted in ME.
The other subsections speak of farm, tractors, antique autos, farm trucks, island vehicles, moped or motorized bicycle or tricycle, fish trucks, experimental motor vehicles, low speed vehicles and wood trackers are all listed as exempted from inspection in the remaining subsections except for the one that is of interest in your situation.
Finally subsection 9 relates to your son's situation. Here it notes that a motor vehicle registered in this State displaying a valid certificate of inspection from another state or a federally approved commercial vehicle inspection program for one year after the date of inspection is exempt.
So your son did not have 30 days to get his inspection sticker renewed once he returned to the state, unless it was 30 days or less from the expiration of the sticker, but he could have asked for a temporary permit from law enforcement or obtained an inspection sticker from Massachusetts so that his car was still legal.
If you have more questions about your son's fine or penalties associated with expired inspection ticket contact the court listed on the ticket. As for the laws associated with an expired inspection sticker contact the ME BMV or Maine State Police.
For Maine car insurance prices, follow this link.