A former Special Branch informer has pleaded guilty to the murder of prominent Belfast solicitor Pat Finucane at his home in 1989.
Ken Barrett, who is 41, was one of two gunmen who shot dead Mr Finucane at his home in the north of the city.
He is expected to be sentenced on Friday.
In a report issued last year, the Commissioner of the Metropolitan Police, Sir John Stevens, found evidence that security forces in the North colluded with loyalist paramilitaries in carrying out the murder.
Nationalist and republican leaders were united in their call for a public inquiry into the murder.
The SDLP leader Mark Durkan said the last vestige of an excuse for failing to hold a public inquiry into the murder of Pat Finucane had now been stripped away.
Sinn Féin President Gerry Adams said that the guilty plea by Ken Barrett had removed the bogus argument which the British government had been using to prevent a full independent inquiry into the murder of Mr Finucane from going ahead.
Mr Adams said he had been in contact with the British government to press for an immediate announcement of a full independent inquiry.
