In Baxstrom v. Herold, the U.S. Supreme Court ruled that it was unconstitutional to deny a prisoner nearing the end of his sentence equal protection under law by transferring him to a mental institution without review or jury trial. The case involved Russell Baxstrom who had been convicted and sentenced for arson in New York State but was transferred directly from prison to a civil hospital upon completion of his term due to mental illness, without any hearing or judicial determination on his dangerousness as required for other mentally ill individuals not coming out of prison system. The court held that this violated both Equal Protection Clause and Due Process Clause of the Fourteenth Amendment because there were no reasonable grounds for treating prisoners differently than all others when committing them indefinitely into psychiatric facilities.

In the dissenting opinion for Baxstrom v. Herold, Justice Harlan argued that the majority's decision failed to consider the state's legitimate interest in protecting society from dangerous individuals. He contended that New York State law provided a rational basis for treating civilly committed patients differently from criminally committed ones because they posed different levels of risk to public safety. The fact that some people might be wrongly classified did not mean the entire system was unconstitutional; instead, it suggested a need for better procedures to ensure accurate classifications. Furthermore, he disagreed with the majority's interpretation of equal protection rights under Fourteenth Amendment and believed their ruling would lead to unnecessary litigation over other differences between civil and criminal commitment processes.