TMA70/S46 (2) provides that determinations by Commissioners in
any proceedings shall be final and conclusive. The appeal cannot be
re-opened by either party unless the Commissioners decide to
exercise their power to review a previous determination (Regulation
17 of SI1994/1812). This remains true even if a case on the point
in dispute is decided in connection with some other assessment. A
payment of tax `under protest' does not in any way keep the case
open. A determination may, of course, also be altered later by the
Courts if, following the Commissioners' decision, a case is
requested (see AH) within the prescribed time limit.
This finality applies only to the particular point before the
Commissioners. Per TMA70/S46 (2) the Commissioners’
determination is `Save as otherwise provided in the Taxes
Acts...'.. Not only can a decision of Commissioners be varied by
the Courts (TMA70/S56 (6) but other provisions may allow the
amendment of an assessment etc which has been determined on appeal,
e.g. the various loss relief provisions (see below).
As to a claim for error or mistake relief under TMA70/S33 in
respect of an assessment etc, the amount of which has been
determined on appeal, see AH.
Finality under TMA70/S46 (2) does not necessarily preclude the making of a loss claim for the year concerned. If the question of the availability of a loss did not form part of the original appeal there is no reason why a loss relief claim cannot be made and given effect to, subject to the time limit and other conditions of the particular relieving section and even though the amount of assessable profits may have been determined by the Commissioners. For example, following the confirmation of an estimated Revenue assessment by the Commissioners the taxpayer and HMRC may agree a loss for the same period to be set against his income including the income in the confirmed assessment. Alternatively a claim may be made to have the loss carried forward.
