He had been investigated by every Garda specialist unit since he was a teenager. He was present at the fatal stabbing of Declan Gavin in August 2001 in Crumlin, Dublin. He was called as a witness in the trial of Brian Rattigan for the killing, but said he had seen nothing. David Byrne had been arrested many times and was a suspect in the murder of Gary Bryan in Walkinstown in 2006. In January 2016 Gardaí had a special policing plan put in place for the following month when two boxing events would be attended by members of a criminal gang associated with Christy Kinahan. The Kinahan gang have a long association with boxing both in Dublin and Marbella.
Shooting
On 5 February 2016 there was to be a boxing match for the WBOEuropean Lightweight title between Jamie Kavanagh and Antonio João Bento at the Regency Hotel in Whitehall, Dublin. At the weigh-in there was an organised armed attack; the match was cancelled after the shooting. There were at least four attackers with masks, army style-helmets and flak jackets, two of whom were disguised as members of the Garda Emergency Response Unit and armed with AK-47s. An associate of the Kinahan cartel, David Byrne was shot dead; security sources said that the gang had intended to kill others. Two men were injured and taken to the Mater Private Hospital and Beaumont Hospital. After the attack, security camera recordings suggested that six people had been involved, including a man disguised as a woman. The attackers escaped in a Ford Transit van which was later found burnt-out. One line of investigation is that the shooting was in revenge for the murder of Gary Hutch in Spain in September 2015.
Funeral
Because of the length of time Byrne's body would be waked at his parents' house before the funeral, special security measures were put in place. The funeral was held at the Church of St Nicholas of Myra, Francis Street. Gardaí checked the church before and after the ceremony for explosives but the funeral passed without incident and the hearse went to Mount Jerome Cemetery.
Suspect
Shortly after the shooting a call was placed to the BBC saying that the Continuity IRA had carried out the attack because Byrne had been involved in the four years before. However, the Continuity IRA later stated that it was not responsible. On 18 May 2016 Patrick Hutch, the brother of Gary Hutch, was charged at the Criminal Courts of Justice with the murder of David Byrne. There was no application for bail; the defendant was granted legal aid and remanded to appear in Clover Hill District Court on 25 May. The trial of Patrick Hutch for murder and possession of firearms was later set for January 2018 at the non-jury Special Criminal Court; he was denied bail. On 20 February 2019, all charges against Patrick Hutch were dropped and he walked free from court. To date, nobody has been convicted of David Byrne's death. In October 2019the High Court ordered the Director of Public Prosecutions to provide transcripts of the collapsed trial to the Garda Síochána Ombudsman Commission.
Subsequent events
The hotel was renamed the Bonnington in October 2017. The renaming had been considered before the shooting, but the process was accelerated after it.
