In the past, wrongful convictions were seen as a local problem largely undeserving of national or international attention. Very different legal systems have shared a common approach of emphasizing the finality of criminal convictions, thereby making it very difficult to claim innocence by relying on new evidence uncovered post-trial. While international law guarantees a right to a fair trial, a presumption of innocence, and a right to appeal, no international human rights norms clearly obligate countries to allow defendants to meaningfully assert post-trial claims of innocence. Today, the procedures and attitudes toward claims of innocence that rely on newly discovered evidence are in flux as more countries have adopted broader remedies for convicts to claim innocence.
Brandon L. Garrett, Towards an International Right to Claim Innocence, 105 California Law Review 1173-1221 (2017)