In June 1990 he was sentenced to life imprisonment at Maghaberry for helping the Provisional IRA kill colleague Brian Armour two years previously.
Alleged former IRA member Sean O'Callaghan, who became an informer for the Garda Síochána, was a fellow inmate of Hanna whilst both were serving their respective sentences at Maghaberry.
According to Sean O'Callaghan, Hanna's former inmate at Maghaberry, he was already a member of the illegal loyalist paramilitary organisation, the Ulster Volunteer Force (UVF).
[1] He allegedly helped the UVF to smuggle a bomb inside the Crumlin Road Gaol in order to kill an IRA prisoner.
[6] According to journalist Liam Clarke, Brown inveigled Hanna into providing her with information on top loyalists and his prison officer colleagues by using a mixture of "blackmail, political argument and seduction".
Hanna claimed he was warned by the IRA that if he did not use his senior position inside the Maze to help them, his "wee grandson might be coming home in a brown box".
[8] It was widely believed by most people, including RUC Chief Constable Sir John Hermon, that McMichael was set up by his fellow associates in the UDA.
Racketeer and UDA "fundraiser" James Craig was shot dead by the Ulster Freedom Fighters (UFF) for allegedly helping the IRA to kill McMichael.
[9] In 1988, Hanna arranged for the killing of a fellow prison officer Brian Samuel Armour with whom he had had a falling-out and sought to get revenge.
[11] In 1992, she and two men were caught with booby-trap bombs in their car, and on 10 September 1993, Brown received a 20-year prison sentence for conspiracy to murder.
Believing O'Callaghan was still part of the organisation, Hanna gave him a list containing the names and addresses of high-ranking RUC officers and prison officials which was to be forwarded to the IRA.