New argument would involve findings of fact

The First-tier Tribunal had dismissed the taxpayer’s appeal concerning the availability and timing of US tax relief to Lloyd’s underwriters and whether the validity of HMRC’s enquiry because it had not complied with aspects of TMA 1970. The taxpayer obtained permission to appeal to the Upper Tribunal.

The point to be appealed was whether a notice of enquiry not posted to the taxpayer’s address in accordance with TMA 1970 s 115 was properly served and whether it was received. HMRC disputed that these points amounted to errors of law but also raised a new argument to which the taxpayer objected on the basis it had not been argued before. The argument was that the taxpayer was estopped by convention from denying that a valid enquiry had been opened in accordance with the Supreme Court’s decision in Tinkler v CRC [2021] STC 1546.

The Upper Tribunal...