18.—(1) This Article and Article 19 apply in respect of proceedings for an offence under Articles 14 to 16 of the Order of 1995 (driving offences connected with drink or drugs); and expressions used in this Article and Article 19 have the same meaning as in Articles 14 to 21 of that Order.
(2) Evidence of the proportion of alcohol or any drug in a specimen of breath, blood or urine provided by the accused shall, in all cases (including cases where the specimen was not provided in connection with the alleged offence) be taken into account; and, subject to paragraph (3), it shall be assumed that the proportion of alcohol in the accused’s breath, blood or urine at the time of the alleged offence was not less than in the specimen.
(3) That assumption shall not be made if the accused proves—
(a)that he consumed alcohol before he provided the specimen and—
(i)in relation to an offence under Article 14, after the time of the alleged offence, and
(ii)otherwise, after he had ceased to drive, attempt to drive or be in charge of a vehicle on a road or other public place, and
(b)that had he not done so the proportion of alcohol in his breath, blood or urine would not have exceeded the prescribed limit and, if it is alleged that he was unfit to drive through drink, would not have been such as to impair his ability to drive properly.
(4) A specimen of blood shall be disregarded unless it was taken from the accused with his consent by a medical practitioner.
(5) Where, at the time a specimen of blood or urine was provided by the accused, he asked to be provided with such a specimen, evidence of the proportion of alcohol or any drug found in the specimen is not admissible on behalf of the prosecution unless—
(a)the specimen in which the alcohol or drug was found is one of 2 parts into which the specimen provided by the accused was divided at the time it was provided, and
(b)the other part was supplied to the accused.