(1) If any of subsections (2) to (5) applies a constable may require a person to co-operate with any one or more preliminary tests administered to the person by that constable or another constable.
(2) This subsection applies if a constable reasonably suspects that the person—
(a) is driving, is attempting to drive or is in charge of a motor vehicle on a road or other public place, and
(b) has alcohol or a drug in his body or is under the influence of a drug.
(3) This subsection applies if a constable reasonably suspects that the person—
(a) has been driving, attempting to drive or in charge of a motor vehicle on a road or other public place while having alcohol or a drug in his body or while unfit to drive because of a drug, and
(b) still has alcohol or a drug in his body or is still under the influence of a drug.
(4) This subsection applies if a constable reasonably suspects that the person—
(a) is or has been driving, attempting to drive or in charge of a motor vehicle on a road or other public place, and
(b) has committed a traffic offence while the vehicle was in motion.
(5) This subsection applies if—
(a) an accident occurs owing to the presence of a motor vehicle on a road or other public place, and
(b) a constable reasonably believes that the person was driving, attempting to drive or in charge of the vehicle at the time of the accident.
(6) A person commits an offence if without reasonable excuse he fails to co-operate with a preliminary test in pursuance of a requirement imposed under this section.
(7) A constable may administer a preliminary test by virtue of any of subsections (2) to (4) only if he is in uniform.
(8) In this section—
(a) a reference to a preliminary test is to any of the tests described in sections 6A to 6C, and
(b) “traffic offence” means an offence under—
(i) a provision of Part II of the Public Passenger Vehicles Act 1981 (c. 14),
(ii) a provision of the Road Traffic Regulation Act 1984 (c. 27),
(iii) a provision of the Road Traffic Offenders Act 1988 (c. 53) other than a provision of Part III, or
(iv) a provision of this Act other than a provision of Part V.