Convicted killer Christopher Robinson had tried to convince two other republican groups to murder prison officer Adrian Ismay, prior to the fatal New IRA attack in March 2016.
Mr Ismay and Robinson knew each other as they both volunteered for St John's Ambulance.
In a police interview from hospital just days before his death, Mr Ismay said he and Robinson "never had cross words" and "got on well" during their three to four years volunteering together.
However, the spiteful Robinson was said to have been envious of Mr Ismay's popularity with the other volunteers and set out to pass information about his movements to an armed dissident group.
Given he worked in the training college and not in Maghaberry - where the dissident prisoners are housed - Mr Ismay did not consider himself to be in any real danger and was quite open about his profession and where he lived.
He did not routinely check under his van, which was fitted with an undercar bomb that exploded causing injuries that led to his death 11-days later.
This made him the softest of targets.
While Robinson had 17 previous convictions this had no significant bearing on his sentencing.
He was not an official member of the New IRA at the time when he offered them information on Mr Ismay. In fact, they were not the first dissident group he approached.
Others, including a senior member of the Continuity IRA and the leadership of Oglaigh na hEireann rejected his offer of information on the prison officer, saying they did not considered him a legitimate target.
Sources say the idea floated by Robinson was rejected by the other organisations who felt targetting Mr Ismay would lead to a public backlash.
He finally convinced the New IRA to help kill the prison officer.
Robinson was known to be a bully. He savagely beat a terminally ill neighbour of his in Divis Tower in west Belfast.
The man who had cancer was forced to leave his home for a time in the last months of his life out of fear of the 50 year old, who the court was told has a history of alcohol abuse and cannabis misuse.
Among seasoned republicans in Belfast he was treated with disdain. He once confronted a former republican prisoner on the Falls Road screaming that Sinn Féin were traitors and that dissident prisoners were being 'interned by remand'.
Onlookers noted that Robinson was on bail for murder at the time and wearing an electronic tag on his ankle while the older man he was harassing had spent several years interned in Long Kesh without trial.
He also had a reputation as being volatile among Belfast's gay community. He had signed up to a number of gay dating sites and used heavily filtered pictured to meet younger men who were unaware of his violent background.
However, he quickly became known as being an aggressive drunk and was barred from a number of city centre gay clubs.
Yesterday Robinson was sentenced to life and told he will serve a minimum jail term of 22 years. He is currently accommodated on the Roe 4 landing of Maghaberry with the rest of the New IRA prisoners.
