In law, a conviction is the verdict that usually results when a court of law finds a defendant guilty of a crime. The opposite of a conviction is an acquittal (i.e. "not guilty"). In Scotland and in the Netherlands, there can also be a verdict of "not proven", which counts as an acquittal. There are also cases where the court orders that a defendant not be convicted, despite being found guilty; in England, Wales, Canada, Australia and New Zealand the mechanism for this is a discharge.
For a host of reasons, the criminal justice system is not perfect, and sometimes guilty defendants are acquitted, while innocent people are convicted. Appeal mechanisms and post conviction relief procedures may mitigate the effects of a conviction to some extent. An error which results in the conviction of an innocent person is known as a miscarriage of justice.
After a defendant is convicted, the court determines the appropriate sentence as a punishment. Furthermore, the conviction may lead to results beyond the terms of the sentence itself. Such ramifications are known as the collateral consequences of criminal charges.
A minor conviction is a warning conviction, and it does not affect the defendant but does serve as a warning.
A history of convictions are called antecedents, known colloquially as "previous" in the United Kingdom, and "priors" in the United States and Australia. The history of convictions also shows that a minor law conviction can be prosecuted as any individuals punishment.