ECJ rules in favour of Irish murderer Graham Dwyer in phone data dispute

Dwyer has challenged Ireland's use of mobile metadata in his 2015 conviction for killing Elaine O'Hara

The European court of justice has ruled in favour of a convicted murderer who challenged Ireland's use of mobile phone metadata in his conviction, with potential implications for criminal investigations across Europe.

The Luxembourg-based court said on Tuesday that Ireland's system of retaining and accessing mobile phone metadata - which helped secure Graham Dwyer's conviction - breached European Union law.