In Shillitani v. United States, the Supreme Court ruled on whether a federal court could indefinitely imprison someone for contempt until they complied with an order to testify before a grand jury. The case involved two individuals who were held in civil contempt after refusing to answer questions from a grand jury investigating organized crime, despite being granted immunity from prosecution based on their testimony. They argued that their imprisonment was unlawful because it was not limited by any specific duration and thus violated their constitutional rights against cruel and unusual punishment. The Supreme Court upheld the lower courts' decisions but clarified that such imprisonment should be viewed as coercive rather than punitive; therefore, if it becomes clear that coercion is not going to compel compliance (for example, if the term of the grand jury has ended), then continued confinement would become punitive and violate due process rights under the Fifth Amendment. This decision established important guidelines for how long someone can be jailed for civil contempt in federal cases.

In the dissenting opinion for Shillitani v. United States, Justice Harlan argued that the majority's decision to allow a contemnor to purge himself of contempt at any time before his sentence is completed undermines the authority of federal courts. He believed this ruling would encourage disrespect and noncompliance with court orders by allowing individuals who are held in contempt to avoid punishment simply by complying after they have been found guilty. Furthermore, he disagreed with the majority's interpretation of Rule 42(a) and (b), arguing that these rules were intended to distinguish between different types of contempt rather than provide alternative methods for dealing with all forms of contemptuous behavior. In essence, Justice Harlan was concerned about preserving judicial authority and ensuring respect for court orders.