The Supreme Court has ordered a total recount of votes cast in the 2014 local elections for the Listowel electoral area in North Kerry, in a judgment that has implications for future elections.
In a unanimous decision, the court upheld a claim by former Senator Dan Kiely that there was a mistake in the conduct of the local election in Listowel, rendering it unlawful.
Four of the five judges ruled there should be a recount.
The central issue in the case was whether a ballot paper which had a sequence of preferences, not starting with one could be deemed a valid vote.
The court heard that election observers had noticed that on days where there was more than one election, many people cast their first and second preferences on one ballot paper and put third, fourth and fifth preferences on the other ballot paper.
A Memorandum of Guidance for Local Authority Returning Officers says officers are entitled on multiple elections days to accept such ballot papers.
In Dan Kiely's case, the local elections took place on the same day as the European elections.
Mr Kiely had argued that because there was no mark on the disputed ballot papers indicating a voter's first preference, they should be excluded.
The Supreme Court found in his favour and ordered a recount.
Mr Kiely narrowly lost out in a battle for the last seat in his area.