With a base in Portadown, the Mid Ulster UVF had an unrivalled reputation for sectarian violence during the Troubles.
Alan Oliver is believed to have joined the organisation in the mid-1980s, at a time when loyalist paramilitaries were stepping up their sectarian murder campaign.
Collusion with security forces is thought to have been rife, with members of the RUC and UDR providing intelligence on targets.
MI5 has also been accused of helping supply killer gangs with weapons and managing its own loyalist agents.
The Mid Ulster unit formed the backbone of the infamous Glenanne Gang, which included members of the RUC and UDR.
It is thought to have been responsible for killing around 120 people, mostly Catholics, in the 1970s.
In the late 1980s a large number of Czech-made VZ-58 assault rifles and handguns were used in attacks linked to Oliver.
Like many loyalists in Mid Ulster at the time, he is also believed to have worked for British intelligence.
Other leading members of the UVF are understood to have been state agents with some working for several agencies at the same time.
One of these was Robin ‘The Jackal’ Jackson who oversaw a sectarian killing spree in Mid Ulster.
During his time in the UVF Oliver maintained a relatively low profile compared to some of his companions.
Wright often courted the press and at the height of the Drumcree crisis in Portadown was regularly seen in the company of Mark 'Swinger' Fulton, also a seasoned sectarian killer.
However, when Wright broke away from the UVF in 1996 to form the Loyalist Volunteer Force, it is believed that Oliver did not follow him into its ranks.
According to his own testimony it was around this time that he started “to wonder what was it all about”.
It is believed Oliver spoke to the police Historical Enquiries Team but refused to make official statements unless he was granted immunity from prosecution. He has publicly denied working with the HET.
