Former Presidential candidate Séan Gallagher is taking legal proceedings against RTÉ arising from the Frontline Presidential Debate.
In a statement, Mr Gallagher's solicitor said his client would be seeking a declaration from the High Court that the programme was unfair and seriously damaged his electoral prospects.
In March, the Broadcasting Authority of Ireland upheld a complaint made by Mr Gallagher relating to the debate, which was broadcast on 24 October.
It said the broadcast of a tweet incorrectly attributed to the official 'Martin McGuinness for President' twitter account was unfair to the complainant.
