Sch 2A para 14
(1) Where a non-intimate sample has been taken from a person under section 63 on two occasions in relation to any offence, he may not under this Schedule be required to attend a police station to have another such sample taken from him under that section in relation to that offence on a subsequent occasion without the authorisation of an officer of at least the rank of inspector. (2) Where an authorisation is given under sub-paragraph (1) above— (a) the fact of the authorisation, and (b) the reasons for giving it, shall be recorded as soon as practicable after it has been given.