A miscarriage of justice occurs when an unfair outcome occurs in a criminal or civil proceeding, such as the conviction and punishment of a person for a crime they did not commit. Miscarriages are also known as wrongful convictions. Innocent people have sometimes ended up in prison for years before their conviction has eventually been overturned. They may be exonerated if new evidence comes to light or it is determined that the police or prosecutor committed some kind of misconduct at the original trial. In some jurisdictions this leads to the payment of compensation.

A false confession is an admission of guilt for a crime which the individual did not commit. Although such confessions seem counterintuitive, they can be made voluntarily, perhaps to protect a third party, or induced through coercive interrogation techniques. When some degree of coercion is involved, studies have found that subjects with highly sophisticated intelligence or manipulated by their so-called "friends" are more likely to make such confessions. Young people are particularly vulnerable to confessing, especially when stressed, tired, or traumatized, and have a significantly higher rate of false confessions than adults. Hundreds of innocent people have been convicted, imprisoned, and sometimes sentenced to death after confessing to crimes they did not commit—but years later, have been exonerated. It was not until several shocking false confession cases were publicized in the late 1980s, combined with the introduction of DNA evidence, that the extent of wrongful convictions began to emerge—and how often false confessions played a role in these.