A few Goofs I spotted
The film is set in 1983, yet the Milltown Massacre of 1988 is shown on TV, by which time the Supergrass system had been abandoned.
The official computer record says Gingy served time in Long Kesh in 1981, when it should refer to the Maze.
A couple of times characters,(one a policeman, who wouldn't regard Britain as a foreign country), refer to going to the UK, when Northern Ireland is part of the UK. They should have referred to England or Great Britain.
Lastly, I know a bit of dramatic licence was used, but in the climax a courtroom that noisy and rowdy would have been cleared by the judge.