[5] The two, John Weir and Billy McCaughey, implicated some of their colleagues in a range of crimes including giving weapons, information and transport to loyalist paramilitaries as well as carrying out shooting and bombing attacks of their own.

[7] According to one subsequent report, at the time of the 1982 shootings, the HMSU that had been active in the constabulary's southern region comprised two dozen men, working in field teams of six, travelling in pairs of specially armoured unmarked Ford Cortinas, the front passenger with a Sterling submachine gun, the rear passenger a Ruger rifle, and all three including the driver were armed with pistols.

According to reports, as uncovered by the Stalker Inquiry, the units operated almost as a law unto themselves, taking orders only from a small group at Gough Barracks in Armagh that was in charge of tasking and co-ordination, who in turn answered only to Special Branch at constabulary headquarters at Knock.

Members generally refused to recognise the authority of senior officers not in the unit, a constable on one occasion telling a CID detective to leave the site and come back after he had had a meal.

[12] The HMSU continued to take part in "rapid reaction" duties, including raids on suspected paramilitary properties, and spearheading riot control.

[citation needed] On 4 November 2001, the RUC was reformed and renamed the PSNI following recommendations of the 1999 Independent Commission on Policing for Northern Ireland report implementing the terms of the 1998 Good Friday Agreement.

[18][19] HMSU officers undergo a 26-week training programme including firearms, unarmed combat, roping, driving, close personal protection and photography.