don't forget, the breathalyser test is simply forming part of the grounds for how the constable will proceed, as you ca see below, you don't need to be breathalysed to be arrested for suspicion of drink drive.....
Motor vehicles: drink and drugs
4 Driving, or being in charge, when under influence of drink or drugs
(1) A person who, when driving or attempting to drive a motor vehicle on a road or other public place, is unfit to drive through drink or drugs is guilty of an offence.
(2) Without prejudice to subsection (1) above, a person who, when in charge of a motor vehicle which is on a road or other public place, is unfit to drive through drink or drugs is guilty of an offence.
(3) For the purposes of subsection (2) above, a person shall be deemed not to have been in charge of a motor vehicle if he proves that at the material time the circumstances were such that there was no likelihood of his driving it so long as he remained unfit to drive through drink or drugs.
(4) The court may, in determining whether there was such a likelihood as is mentioned in subsection (3) above, disregard any injury to him and any damage to the vehicle.
(5) For the purposes of this section, a person shall be taken to be unfit to drive if his ability to drive properly is for the time being impaired.
(6)
A constable may arrest a person without warrant if he has reasonable cause to suspect that that person is or has been committing an offence under this section.
(7)
For the purpose of arresting a person under the power conferred by subsection (6) above, a constable may enter (if need be by force) any place where that person is or where the constable, with reasonable cause, suspects him to be.
(8) Subsection (7) above does not extend to Scotland, and nothing in that subsection affects any rule of law in Scotland concerning the right of a constable to enter any premises for any purpose.
5 Driving or being in charge of a motor vehicle with alcohol concentration above prescribed limit
(1) If a person—
(a) drives or attempts to drive a motor vehicle on a road or other public place, or
(b) is in charge of a motor vehicle on a road or other public place,
after consuming so much alcohol that the proportion of it in his breath, blood or urine exceeds the prescribed limit he is guilty of an offence.
(2) It is a defence for a person charged with an offence under subsection (1)(b) above to prove that at the time he is alleged to have committed the offence the circumstances were such that there was no likelihood of his driving the vehicle whilst the proportion of alcohol in his breath, blood or urine remained likely to exceed the prescribed limit.
(3) The court may, in determining whether there was such a likelihood as is mentioned in subsection (2) above, disregard any injury to him and any damage to the vehicle.
