Finucane had represented several high-profile IRA members, most notably hunger striker Bobby Sands, in cases against the British government in the 1980s. Though there was little doubt as to the identity of those directly involved in the murder – the loyalist paramilitary group Ulster Defense Association (UDA) claimed responsibility soon afterward, alleging that Finucane was a member of the IRA – there has long been suspicion that the government also had a role.
UDA member and police informant Ken Barrett was convicted of the murder in 2004. He confessed to police in a sting operation, having previously admitted the killing to BBC reporters. The reporters secretly recorded him saying that Finucane "would have been alive today if the peelers [police] hadn't interfered," as the UDA considered killing lawyers to be "off limits."
It later came to light that Mr. Barrett had confessed to police in 1991, but the tape of the interrogation disappeared.
Finucane's murder continues to hang over Northern Ireland and has long been viewed by Irish nationalists and republicans as evidence not only of police and British Army infiltration into loyalist groups, but of their active direction of loyalist killing campaigns. The weapon used to kill Finucane had been stolen from the Army and was later discovered by police, who handed it back to the Army rather than keeping it as evidence, despite full knowledge that it was the murder weapon.
The killing of Finucane, along with others, such as that of lawyer Rosemary Nelson in 1999, also by loyalists, are totemic events for nationalists who say they demonstrate the Northern Irish state was openly hostile to them. A 2011 report into Ms. Nelson's murder found no evidence of collusion, but said police "legitimized her as a target" by assaulting her two years previously.