Section 12 of the Road Traffic Act, 1994 (substituted by section 2 of the Road Traffic Act, 2003) provides that a member of An Garda Síochána may request the provision of a preliminary breath specimen or the provision of a blood or urine specimen from a person who the member is of the opinion has been involved in a collision. Section 15 of the Road Traffic Act, 1994 provides a power to require the provision of a blood or urine specimen from the driver of vehicle who has been admitted to hospital following a collision, where an opinion has been formed by a member of An Garda Síochána that the driver has consumed an intoxicant.
The Headquarters Directive referred to sets out the Commissioner's policy for the enforcement by An Garda Síochána of this legislation. Members of An Garda Síochána have been directed that, as a matter of policy, section 12 should be exercised (i) in all instances where a Garda is of the opinion intoxicating liquor has been consumed or (ii) where a Garda is of the opinion that the person in charge of a vehicle is, or has, with the vehicle, been involved in a collision, unless that Garda is of the opinion that the person has not consumed intoxicating liquor, and unless circumstances, such as the need to render medical assistance, require otherwise. Members of An Garda Síochána have also been directed that section 15 should be exercised where the driver of a vehicle has been admitted to hospital following a collision and a Garda has formed the opinion that the driver has consumed an intoxicant.
Section 4 of the Road Traffic Act 2006 provides for the testing of drivers, without individual suspicion that the driver has consumed alcohol. Under the section a member of An Garda Síochána, who is on duty at a checkpoint established under an authorisation, may stop any mechanically propelled vehicle at the checkpoint and, without prejudice to any other powers (including the powers under section 12 of the Act of 1994) conferred on him or her by statue or at common law, may require a person in charge of the vehicle to undergo a breath test.