Mobile data retention practices used in the case against Graham Dwyer, who was convicted of murder, breached European law, Europe's top court has ruled.
The Court of Justice of the EU (CJEU) ruled that EU law precludes the general and indiscriminate retention of traffic and location data relating to electronic communication for the purpose of combating serious crime.
Mobile phone data was used prominently by the prosecution in Dwyer's trial for the murder of childcare worker Elaine O'Hara in 2015.
Dwyer pleaded not guilty to the charge but was convicted and sentenced to life in prison for killing Ms O'Hara in 2012.
The case was referred to the CJEU by the Irish Supreme Court, following a successful challenge by Dwyer to the retention and accessing of his mobile phone data.
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