The United States Parole Commission v. Geraghty case in 1979 revolved around the issue of mootness in class action lawsuits. The respondent, John Geraghty, an inmate who had been denied parole under guidelines established by the U.S. Parole Commission, filed a lawsuit challenging these guidelines as unconstitutional and sought to represent a class of similarly situated prisoners. However, his individual claim became moot when he was released from prison before the District Court could rule on his motion for class certification. The Supreme Court held that an action brought on behalf of a class does not become moot upon expiration of the named plaintiff's substantive claim if it remains possible for other members' claims to be resolved through litigation or settlement negotiations even after such expiration - thus allowing Geraghty’s appeal despite him no longer being directly affected by parole decisions at time of ruling. This decision clarified that "mootness" did not automatically disqualify cases from consideration and expanded potential scope for future legal actions involving collective groups with shared interests.

In the dissenting opinion for United States Parole Commission et al. v. Geraghty, it was argued that a case becomes moot when there is no longer a live controversy between the parties and thus should not be reviewed by the court. The dissenters believed that since Geraghty had been released from prison, his challenge to parole guidelines became moot because he could no longer benefit personally from any relief granted by the courts. They also disagreed with majority's view on "capable of repetition yet evading review" exception to mootness doctrine as they felt this exception did not apply in this situation where plaintiff’s personal stake ended upon his release from incarceration. Furthermore, they contended that allowing an action to continue based solely on class certification issues would blur traditional jurisdictional boundaries and potentially lead to abuse of judicial process.