UPDATE: Graham Dwyer Has Won His Legal Action Against The State And Garda Commissioner
The former architect, who is originally from Bandon, was convicted by a jury three years ago of the 2012 murder of childcare worker Elaine O’Hara.
Mobile phone data formed a huge part of the trial but Dwyer argued it shouldn’t have been used as it breached his rights.
The High Court has ruled that Irish laws - which allow for mobile phone data to be retained and accessed - breaches EU law.
Dwyer isn't in court for the ruling which is ongoing.
He has already stated his intention to go to the Court of Appeal to challenge his murder conviction.
More from Cork
Woman Cycling Around Ireland Arrives In Cork
She's raising money for the RNLI
Yacht Crew Off Cork Coast Rescued By RNLI Over Bank Holiday Weekend
The crew called for help on Saturday night
Emergency Services Responded To Road Collision In Cork Overnight
The incident happened at Knocknahowla near Ballinclashet.
Death Toll Rises To 290 Following Bombings In Sri Lanka
No group has said it was behind the attack
The Top 4 Things You Need To Know Now
The main stories making the news across Cork
More Steps Need To Be Taken To Tackle West Cork's Homeless Crisis
That's according to Social Democratic candidate Evie Nevin