In the case of Arizonans for Official English and Robert D. Park v. Arizona et al., 1996, the U.S Supreme Court was asked to rule on whether an amendment to the Arizona state constitution making English the official language of all government functions was constitutional or not. The plaintiff, Maria-Kelly Yniguez, a public employee who spoke Spanish in her job at a state agency argued that this violated her First Amendment rights. However, by the time it reached Supreme Court review, Yniguez had left her job rendering moot any relief she could have obtained from litigation since there were no ongoing consequences for past conduct nor future threat due to changed circumstances. Therefore, rather than ruling on its merits or lack thereof regarding free speech issues raised by declaring English as an official language in governmental operations - which would be advisory opinion forbidden under Article III - they vacated prior judgment and remanded with instructions to dismiss based upon mootness doctrine.

In the dissenting opinion for Arizonans for Official English and Robert D. Park v. Arizona et al., Justice Ginsburg argued that the case should have been dismissed as moot, given that respondent Maria-Kelly Yniguez had left her state employment before the Ninth Circuit's en banc decision. She pointed out that there was no live dispute between an employer and employee over a language policy at work when the Supreme Court granted certiorari, thus making it inappropriate to decide on this issue in such circumstances. Furthermore, she disagreed with the majority’s view of standing, arguing instead that petitioners lacked standing because they did not demonstrate any actual or imminent injury from enforcement of Article XXVIII (the amendment declaring English as official language). Lastly, she criticized their broad interpretation of taxpayer standing doctrine which could potentially open floodgates to lawsuits by taxpayers who disagree with government policies but are not directly harmed by them.