特赦，指以行政权免除罪犯全部或部分的服刑。宋代以前中国即存在特赦，有所谓「八议」之同罪异罚之说。学者认为特赦权的开始始于19世纪的英国君主，在司法独立以及国会扩权的时代，是少数专属于君主的特权之一。在不同的国家里，不同的人或组织有下达特赦令的权利，比如国家元首或者议会。在不同国家里对特赦令的定义和理解也各不相同。比如有些国家中（如德国），对个人和对一群人的特赦令有不同的称呼和定义。在有些国家里，特赦令虽然免除被特赦的人的服刑期或服刑的重度，但它并不表示该人已经无罪了。在另一些国家中，特赦令也免除被特赦者的罪行。颁布特赦令的原因一般有以下几种：

Pardon is the postponement of punishment, often with a view to a pardon or other review of the sentence (such as when the reprieving authority has no power to grant an immediate pardon).

Today, pardons are granted in many countries when individuals have demonstrated that they have fulfilled their debt to society, or are otherwise considered to be deserving. Pardons are sometimes offered to persons who are wrongfully convicted or who claim they have been wrongfully convicted. In some jurisdictions, accepting such a pardon implicitly constitutes an admission of guilt (see Burdick v. United States in the United States), so in some cases the offer is refused. Cases of wrongful conviction are nowadays more often dealt with by appeal than by pardon; however, a pardon is sometimes offered when innocence is undisputed to avoid the costs of a retrial. Clemency plays a very important role when capital punishment is applied.