CCM13020 - Discovery Decisions: Meaning of

A discovery decision can only be made where a conclusive decision relating to the entitlement to tax credits is incorrect. The meaning of “conclusive decision” is defined in the legislation.

S20(6) defines a conclusive decision on entitlement, or joint entitlement, as

a. a decision in relation to it under section 18(1), (5), (6) or (9) or 19(3) or a previous decision under this section, or

b. a decision under regulations under section 21 relating to a decision within paragraph (a),

including a decision made on an appeal against such a decision.

The references to decisions under S18 are all to final decisions made after the end of the year on the entitlement for that year. The S19(3) decision is the decision which you are required to make at the end of every enquiry. S21 allows a revised decision to be made where there has been official error.