John Oliver explored how difficult it is to appeal a wrongful conviction in the US, even if there’s compelling evidence of innocence, on Last Week Tonight.
Though the constitution contains the writ of habeas corpus to protect against unlawful imprisonment – “basically, you have a right to challenge your incarceration, and you can do that in state and federal court,” Oliver explained – there’s a major limitation: in general, innocence itself is not an appealable issue.