For the last two days, Graham Dwyer's appeal against his 2015 conviction for the murder of childcare worker Elaine O'Hara, was heard in Dublin's Appeal Court.
She was just 36 when she disappeared in August 2012 and her body was only discovered in a forest in the Dublin Mountains some 13 months later.
But Dwyer is appealing his conviction on a number of grounds including the retention and accessing of data relating to his work mobile phone.
His lawyers say this data was used to link him to other phones and to messages sent to Ms O'Hara. Dwyer wants a retrial.
Irish Independent's Legal Editor, Shane Phelan, was in court for the two-day appeal, and joins presenter Fionnán Sheahan to explain what happened and where it might lead to for Dwyer.