(1) In England and Wales, proceedings for an offence under this Act may be instituted only -
(a) by the Commissioner, or
(b) by or with the consent of the Director of Public Prosecutions.
(2) In Northern Ireland, proceedings for an offence under this Act may be instituted only -
(a) by the Commissioner, or
(b) by or with the consent of the Director of Public Prosecutions for Northern Ireland.
(3) Subject to subsection (4), summary proceedings for an offence under section 173 (alteration etc of personal data to prevent disclosure) may be brought within the period of 6 months beginning with the day on which the prosecutor first knew of evidence that, in the prosecutor's opinion, was sufficient to bring the proceedings.
(4) Such proceedings may not be brought after the end of the period of 3 years beginning with the day on which the offence was committed.
(5) A certificate signed by or on behalf of the prosecutor and stating the day on which the 6 month period described in subsection (3)
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