(1)If an officer of Revenue and Customs discovers that a payment or set-off of tax credit should not have been made or is excessive, the officer may act in accordance with subsection (3) or (4).
(2)For the purposes of subsection (1) it does not matter whether the payment or set-off was excessive when made or became so later.
(3)The officer may make any assessment that in the officer's judgement is needed to recover—
(a)any corporation tax that should have been paid, or
(b)any payment of tax credit that should not have been made.
(4)More generally, the officer may make any assessment that in the officer's judgement is needed to secure that the liabilities to corporation tax (and any liabilities to interest on corporation tax) of the persons concerned are what they would have been if only the correct set-offs and payments had been made.
(5)Subsection (6) applies if—
(a)interest on a payment of tax credit comprised in any franked investment income has been paid under section 826 of ICTA, and
(b)interest should not have been paid on the payment, or should only have been paid on part of it.
(6)An officer of Revenue and Customs may make an assessment for recovering the interest, so far as it should not have been paid.