3. After regulation 20 insert—
20A.—(1) Arrears of council tax are not recoverable if they arise in consequence of an over-entitlement to council tax reduction as described in paragraph (2).
(2) This paragraph applies to an over-entitlement which arises in consequence of an official error where the claimant or a person acting on their behalf or any other person to whom the council tax reduction is awarded could not have reasonably been expected to realise that it was an over-entitlement at the time it arose or upon any subsequent notification of entitlement.
(3) In this regulation, “over-entitlement” means an amount of council tax reduction which was awarded and to which there was no entitlement (whether on the initial decision or as subsequently reviewed or superseded or further reviewed or superseded).
(4) In this regulation, “official error” means a mistake, whether in the form of an act or omission, by—
(a)the relevant authority,
(b)an officer or person acting for the relevant authority, or
(c)a person providing services to the relevant authority,
where the claimant, a person acting on their behalf or any other person to whom the council tax reduction is awarded, did not cause or materially contribute to that mistake.”.