(1)A fixed penalty notice may not be issued to a person in relation to a relevant offence arising out of a particular act or omission if—
(a)a fixed penalty notice has previously been issued to the person (and not withdrawn) in relation to the same relevant offence arising out of the same act or omission, or
(b)criminal proceedings—
(i)have been brought against the person for the same relevant offence arising out of the same act or omission, or
(ii)cannot, because of the expiry of relevant time limits for prosecution, any longer competently be brought against the person for the same relevant offence arising out of the same act or omission.
(2)A fixed penalty notice issued in contravention of subsection (1) is of no effect (and, accordingly, the appropriate enforcement authority must repay any amount paid in respect of the notice).