Notices requiring a third party to produce documents, issued by the Inland Revenue during tax investigations. s.20(3) TMA 1970.The draft notices issued by the Revenue in this case were permitted by s.20(8A) TMA since although the documents requested were conjectural and described only in general terms, nevertheless they were described in the notices within the meaning of s.20(8D) TMA; furthermore the requirement for the consent of the Special Commissioner under s.20(8A) provided a sufficient safeguard against the misuse of the Revenue’s power in this regard.R v. O’Kane and Clarke, ex p. Northern Bank Ltd disapproved in partDavid Goldberg KC appeared for the taxpayerPetition for leave to appeal to House of Lords refused