Some 21 are still being investigated, while 36 have reached a private settlement with Revenue and customs and agreed to pay £605,000 between them. None of the barristers concerned have been prosecuted, and their names have not been made public.

The revelation appeared in a Committee report, HMRC: Tackling the Hidden Economy, published in December 2008. HMRC estimates it loses about £2bn worth of tax revenue each year in the hidden economy.