Jackson v. Indiana, 406 U.S. 715 (1972), was a landmark decision of the United States Supreme Court that determined a U.S. state violated due process by involuntarily committing a criminal defendant for an indefinite period of time solely on the basis of his permanent incompetency to stand trial on the charges filed against him.

They claimed that petitioner Jackson was being denied equal protection because, without the criminal charges pending against him, the State would have been required to proceed using Indiana's statutory provisions for the feeble-minded or for the mentally ill.

It held that the state of Indiana cannot constitutionally commit the petitioner for an indefinite period of time on the sole grounds that he was incompetent to stand trial on the charges filed against him, thus violating both the equal protection and due process clauses of the Fourteenth Amendment.

[2] Therefore, the Court ruled that Indiana's indefinite commitment of a criminal defendant solely because he lacks the capacity to stand trial violates due process.

Such a defendant cannot be held more than the reasonable period of time necessary to determine whether there is a substantial probability that he will attain competency in the foreseeable future.

[2] Before this landmark case, pre-trial involuntary commitment of incompetent individuals often meant lengthy or even lifetime confinement in a maximum security institution with little concern for treatment.

However, the Court offers only general guidelines and by 1994, twenty years after the case, 32 states still had not enacted periodic judicial review of incompetent detainees.