By Ann O'Loughlin

Graham Dwyer wants the High Court to strike down provisions of the law that allowed data from mobile phones be used by prosecutors as evidence during his trial for the murder of Elaine O'Hara.

Dwyer (45) was sentenced to life imprisonment in April 2015 after a jury at the Central Criminal Court found him guilty of Ms O'Hara's murder.

He has brought a challenge against provisions of 2011 Communications Act which allowed Gardaí investigating Ms O'Hara's death to obtain and use certain data, including phone records, as evidence against him during his lengthy trial.

He claims provisions of that Act are unconstitutional and breached his rights, including his right to privacy.

Today, Dwyer's lawyers told Mr Justice Tony O'Connor certain provisions of the Communications (Retention of Data) Act 2011 Act breach his Constitutional rights, European Convention on Human Rights (ECHR) and rights under the Charter of Fundamental Rights of the European Union to privacy and protection of his personal data.

Dwyer (pictured) seeks various declarations in proceedings against the Garda Commissioner, Director of Public Prosecutions, Ministers for Justice and Communications, Ireland and the Attorney General, which oppose the action.

Dwyer's case centres on the European Courts of Justice ECJ's decision in 2014 to strike down the EU directive underlying the 2011 Act.

The State parties reject all of Dwyer's arguments and deny the 2011 Act is incompatible with the Charter, ECHR or the Constitution.

In his action Dwyer seeks declarations including that provisions of the 2011 Act are incompatible with the EU Charter and are repugnant to Articles 40.3.1, 40.3.2 and 40.6.1 of the Irish Constitution.

He also seeks a declaration that provisions of the 2011 Act are incompatible with the State's obligations under Articles 8 and 10 of the ECHR.

He further seeks damages and an order for his legal costs.

Dwyer was not present at the hearing, and is currently incarcerated at the Midlands Prison.

Mr Farrell said his client "is not seeking to challenge his conviction in these proceedings", but that was very much "a live issue" in Dwyer's appeal against his conviction.

Opening the case Remy Farrell SC for Dwyer said in 2014 the European Court Of Justice (ECJ) held that Directive 2006/24/EC which concerns the retention of data was invalid.

The directive was designed to harmonise laws of the EU member states concerning the retention of certain data on electronic communication services on communication networks, such as mobile phone and internet records.

It sought to ensure that all data was available for the prevention, investigation, detection and prosecution of serious crime and required service providers to retain traffic and location data necessary to identify the subscriber or user.

In 2011 the Communications (Retention of Data) Act was enacted by the State.

This Mr Farrell said this was done to give effect to the EU Directive. It permitted a senior Garda to require a service provider to give the gardaí any retained data believed to be required for a probe of a serious offence punishable by imprisonment of a period of 5 years or more.

In 2014 the ECJ found in a case called Digital Rights Ireland Ltd vs The Minister for Communications, Marine and Natural Resources and others that the 2006 EU Directive was invalid.

Counsel said the 2011 Act suffers from the same flaws as the directive.

Counsel said that his client has "a fundamental difficulty" with the "indiscriminate regime" under the Act which allows everyone's data to be retained for two years. He added that they had complaints about the access to this data, particularly the lack of independent oversight in relation to accessing the data.

Counsel said the decision to arrest and charge Dwyer in October 2013 was based to a significant extent on the analysis of the data disclosed to the Gardaí by mobile phone providers under the 2011 Act.

The data analysis concerned the nature of contact between certain phones, including a phone used by Dwyer and "two phones attributed to him by the Prosecution," counsel said.

The evidence included dates, times, who was contacting whom and if it was a text message, and which networks various contacts were routed through, counsel said.

The information allowed the prosecution tell the jury the phones were in certain places at certain times, and the location when the calls and texts were made and received.

Dwyer's lawyers citing the ECJ's decision, applied to the judge presiding at the murder trial, Mr Justice Tony Hunt, to exclude the data and phone analysis evidence.

The Judge dismissed the application and let the evidence go before the jury on the basis the 2011 Act remained in force and had not been challenged.

The trial proceeded and the jury found Dwyer guilty on a unanimous verdict.

The case continues.