Good Cop/Bad Cop

When the Harris family was found brutally murdered, chief investigator David McElligott began an investigation and breathed a sigh of relief when the police's rising star, David Harding, found the murderer's fingerprints and solved the case in just six weeks.
However, McElligott suspected Harding was not a hero and continued his own private investigations. Two years later, federal authorities announced Harding had falsified evidence and perjured himself to bring about a conviction.