Terrible second half to the film

Rating: 5/10 (5 January 2007)

This film certainly wasn't as masterpiece. It was reasonably well filmed and acted, nothing exceptional though. Up to about half way through the film I thought it was very good, however the film then moved into fantasy land after that.
There were so many plot holes and inconsistencies that the film became almost a parody of itself. The quite ludicrous level that the Matt Damon character was able to get away with anything just went too far. This then ruined the film.
To mention a few of the problems:
Why was Sullivan (Matt Damon) motivated to help Costello (Jack N) so much, risking his career, imprisonment and life.
If you have a mole in the Police you would give the case to another department and not randomly nominate some rookie, who is a suspect and then give him full power over the entire team.
Internal Affairs would be investigating the Police unit, searching for the mole
Sullivan already had a history with Costello, surely this could have been easily discovered
You cannot just delete someone's record from a computer (back-ups, audit trail)
Why did Costigan have to meet Sullivan and arrest him 'in person', on a rooftop, which was already a crime scene.
I could go on and on, but basically you get the point. All films stretch reality, but this just went too far and turned the movie into a farce by the end.
5/10