F48[17.— (1) As soon as practicable after it has received a specimen forwarded to it under section 15, the Bureau shall analyse the specimen and may determine, as appropriate, all or any of the following:

(a) the concentration of alcohol in the specimen;

(b) the presence of a drug or drugs in the specimen;

(c) the concentration of a drug or drugs in the specimen.]

(2) Where the Bureau receives 2 specimens of blood so forwarded together in relation to the same person or 2 specimens of urine so forwarded together in relation to the same person, it shall be sufficient compliance with subsection (1) for the Bureau to make an analysis of and determination in relation to one of the 2 specimens of blood or (as may be appropriate) one of the 2 specimens of urine.

(3) As soon as practicable after compliance with subsection (1), the Bureau shall F49[, subject to section 17A(3),] forward to the Garda Síochána station from which the specimen analysed was forwarded a completed certificate in the form prescribed for the purpose of this section and shall forward a copy of the completed certificate to the person who is named on the relevant form under section 15 as the person from whom the specimen was taken or who provided it.

(4) In a prosecution for an offence under this Chapter or under section 4 or 5, it shall be presumed until the contrary is shown that subsections (1) to (3) have been complied with.