Carroll Youngblood (defendant) was convicted in a Texas court of aggravated sexual abuse and was sentenced to life imprisonment and a fine of $10,000. After his conviction was affirmed by the Texas Court of Criminal Appeals, Youngblood filed a petition for a writ of habeas corpus in Texas district court, arguing that the Texas Code of Criminal Procedure did not authorize a fine in addition to a term of imprisonment for his offense and thus his conviction was void. The district court granted Youngblood’s writ. Before the writ could be considered by the Texas Court of Criminal Appeals, the Texas Legislature enacted a law to allow an appellate court to reform an improper verdict that assessed a punishment not authorized by law. Relying on the new statute, the appellate court reformed Youngblood’s conviction by removing the $10,000 fine from his sentence and denied his request for a new trial. Youngblood then filed a petition for a writ of habeas corpus in U.S. District Court claiming Texas’ retroactive law violated the Ex Post Facto Clause. The petition was denied by the district court and the court of appeals reversed. The U.S. Supreme Court granted certiorari to review.