Because police, detectives and forensic scientists are only human, and it's all-too natural to be inexplicably reluctant to admit to – or even to see – some of their mistakes.
DNA testing has overturned many wrongful convictions but the vast majority of criminal cases have no DNA to test. And some of those inmates’ convictions are also flawed.
Almost half the DNA tests conducted at prisoners’ request confirm guilt. Yet many believe that the exceptions more than justify making post-conviction testing widely accessible. And what is often fair or prudent is for Death Row inmates essential.
Fingerprint matching is a vital investigative tool. But despite its legendary aura of infallibility, courtroom claims of fingerprints’ uniqueness are slowly receding.
Amateurs and experts alike overestimate their ability to divine truth and deception. But when criminal investigators do it, it can be very bad news for the accused.
Experts find recurring themes in wrongful convictions. And while some jurisdictions are now creating in-house review units to ensure convictions are righteous, commonly repeated mistakes continue to mar cases.
John Watkins' stash of pornography made him a look like a prime suspect for a rape in police and prosecutors' eyes. How they wrung a confession out of him and convinced a shaky witness to ID him offers textbook examples of how to achieve a wrongful conviction.