The State will appeal the pre-Christmas High Court decision on the retention and use of mobile phone data in an action taken by convicted murderer Graham Dwyer.

State legal teams and the Garda Commissioner are to appeal the High Court's decision that using such data in criminal probes or prosecutions breached EU law and the European Convention on Human Rights.

In the High Court this morning, Mr Justice Tony O'Connor was told by senior counsel Brian Murray that the State would be applying for a ‘leapfrog’ appeal – going straight to the Supreme Court and bypassing the Court of Appeal.

Both sides consented to a stay on the declarations sought by Dwyer taking effect until the appeal is finally determined.

Dwyer was convicted in 2015 of the 2012 murder of childcare worker Elaine O'Hara.

The prosecution used mobile-phone data to show the location of Dwyer's phone at key points.

Gardaí obtained the information under legislation brought in following a European directive, later declared invalid. 

Serious offences

Mr Justice Tony O'Connor found the legislation allowing such data to be kept for probing serious offences was indiscriminate and breached EU law.  

He said that the Court of Justice of the EU had ruled that even tackling serious crime could not justify such data retention.