The Court of Appeal has dismissed prominent republican Thomas 'Slab' Murphy's appeal against conviction for evading tax on profits from farming.

Lawyers for the 67-year-old, whose farm at Ballybinaby, Hackballscross, Co Louth, straddles the border with Northern Ireland, had told the Court of Appeal that Murphy had "nothing to do with cattle farming" and that the authorities "went after" Murphy for tax his brother, Patrick, had already paid.

Murphy had pleaded not guilty at the non-jury Special Criminal Court to nine charges of failing to comply with tax laws in the Republic for the years 1996 to 2004.

The three-judge Special Criminal Court found Murphy guilty on all counts and he was sentenced to 18 months imprisonment on 26 February last year.

Murphy sought to appeal his conviction on 53 grounds of appeal in more than 350 pages of written submissions.

Dismissing Murphy's appeal on all grounds, President of the Court of Appeal Mr Justice Seán Ryan said the court had considered the matter "carefully" and "thoroughly" but had concluded that the appeal be dismissed.