In Carafas v. Lavallee, Warden, 1967, the U.S. Supreme Court ruled that a federal court could still hear an appeal from a state prisoner who had completed his sentence but was still suffering civil disabilities as a result of his conviction. The petitioner in this case was John Francis Carafas, who had been convicted of rape and sentenced to imprisonment for up to fifty years by New York State courts. While serving his term in prison, he filed an application for habeas corpus relief with the Federal District Court claiming that he had not received fair trial due to constitutional violations during the proceedings against him at state level. The lower courts dismissed Carafas' petition on grounds that it became moot when he was released from custody after parole; however, the Supreme Court reversed these decisions stating that even though Carafas' criminal sentence ended upon release from physical confinement (parole), there were ongoing legal consequences or "collateral consequences" resulting from his conviction which included loss of certain civil rights such as voting and holding public office among others. Therefore, despite completion of custodial punishment part of sentencing imposed by law enforcement authorities under jurisdictional purview applicable within respective states across United States territory where individual resides post-release period following incarceration phase ends officially - person's status remains affected adversely due significant impact caused through imposition severe restrictions limiting exercise fundamental democratic privileges enjoyed typically by ordinary citizens without any criminal record history whatsoever.

In the dissenting opinion for Carafas v. Lavallee, Justice Harlan disagreed with the majority's interpretation of federal habeas corpus law. He argued that once a petitioner had served his sentence and was no longer in custody, he could not bring a habeas corpus petition to challenge his conviction because he did not meet the "in custody" requirement under federal law. According to Justice Harlan, this requirement is jurisdictional and cannot be waived or ignored by courts at their discretion. Furthermore, he contended that even if there were lingering collateral consequences from the conviction (such as affecting one’s ability to vote), these did not amount to being “in custody” within the meaning of habeas corpus statute. Therefore, according to him, such cases should be addressed through other legal means rather than expanding the scope of habeas relief beyond its traditional boundaries.