Motor tax is based on the construction and use of a vehicle. In order to qualify for the goods rate of motor tax, a vehicle must be constructed or adapted for use and used solely for the conveyance of goods in the course of trade or business, including agriculture.
Licensing authorities have an obligation under Article 3 of the Road Vehicles (Registration and Licensing)(Amendment) Regulations 1992 to be satisfied that a vehicle is correctly taxed and it is thus open to a motor tax office to seek additional documentation supporting a claim for the goods rate of motor tax. Such documentation may include a certificate of commercial insurance or evidence of registration for VAT purposes or, at the discretion of the licensing authority concerned, any other appropriate documentation that would indicate that the applicant is in trade or business. It is up to the individual concerned to provide whatever evidence is required by the licensing authority in order for it to be satisfied that the applicant is entitled to the goods rate of motor tax, which is effectively a concessionary rate.
Enforcement is primarily a matter for An Garda Síochána and the onus is on an individual driver to satisfy the Gardaí that their vehicle is taxed at the appropriate rate.