An assessment on any person (in this section referred to as “the person in default”) for the purpose of making good to the Crown a F5loss of income tax or capital gains tax attributable to his fraudulent or negligent conduct or the fraudulent or negligent conduct of a person acting on his behalf may be made at any time F6not later than 20 years after the 31st January next following the year of assessment to which it relates.

Where the person in default carried on a trade, profession or business with one or more other persons at any time in the period for which the assessment is made, an assessment in respect of the profits or gains of the trade, profession or business for the purpose mentioned in subsection (1) above may be made not only on the person in default but also on his partner or any of his partners.

If the person on whom the assessment is made so requires, in determining the amount of the tax to be charged for any chargeable period in any assessment made for the purpose mentioned in subsection (1) above, effect shall be given to any relief or allowance to which he would have been entitled for that chargeable period on a claim or application made within the time allowed by the Taxes Acts.

In subsection (3) above, “claim or application” does not include an election under section 257BA of the principal Act (elections as to transfer of married couple’s allowance) F7or under Schedule 13B to that Act (elections as to transfer of children’s tax credit).

Any act or omission such as is mentioned in section 98B below on the part of a grouping (as defined in that section) or member of a grouping shall be deemed for the purposes of subsection (1) above to be the act or omission of each member of the grouping.