Factual error: At the end of the film Rainwood has established his innocence of the drug charges and is happily back at work as a senior mechanic for a large airline. However, part of the sentencing and plea bargain protocols at his arraignment is his previous conviction on a lesser drug charge years before. It goes without saying that he did not advise his employers of this when he started work for them - no airline in the world (even pre 9/11) would hire someone with a drug conviction on their record! Now this is out in the open the airline knows that Rainwood is a convicted drug user (on the lesser, legitimate charge) and that he lied on his original job application. They wouldn't hire him again to sweep the floors.
Factual error: Rainwood exposes Parnell as a bent cop and as a result his conviction is quashed. That can't happen. Rainwood pleaded guilty in a plea bargain so regardless of future events he is guilty in the eyes of the law. He could appeal against the severity of his sentence but his conviction would be upheld, regardless of how unfair that is. (There have been real life incidences of this kind of thing happening).