A long-standing mystery for the Minister for Enterprise, Trade and Employment was solved by the revelations about AIB depositors not paying their DIRT tax.

Mary Harney said last week she had been somewhat mystified by the lack of response to her tax proposals of the late 1980s and early 1990s. In fact some sections of the community, who ought to have known better, were distinctly unenthusiastic, she remembered. Of course, with hindsight, she realised that there had been "a two-tiered tax situation".