Any vehicle intended or adapted for propulsion by mechanical power, irrespective of engine capacity, is considered to be a mechanically propelled vehicle under Road Traffic Legislation when used in a public place. The user of such a vehicle in a public place must have insurance, road tax and a driving licence, and must also wear a helmet when using certain vehicles, with severe penalties under the road traffic laws (including fixed charge notices, penalty points, fines and possible seizure of a vehicle) for not being in compliance with these requirements.
Vehicles used in a public place must also comply with the requirements of the Road Traffic (Construction, Equipment and Use of Vehicles) Regulations 1963 to 2002 and the Road Traffic (Lighting of Vehicles) Regulations 1963 to 1996. These regulations prescribe standards in relation to essential matters such as brakes, steering, mirrors, safety glass, wipers, headlamps, rear lighting, indicators and reflectors. Vehicles not in compliance with these regulations are not, therefore, considered suitable for use in a public place.
For the purposes of the Road Traffic Acts, a "public place" means any public road, and any street, road or other place to which the public has access with vehicles whether as of right or by permission, and whether subject to or free of charge. Road traffic law does not extend to the use of mechanically propelled vehicles on private property.
Enforcement of road traffic legislation is a matter for an Garda Síochána.