In the case of Stringfellow et al. v. Concerned Neighbors in Action et al., 1986, the United States Supreme Court ruled on whether a community group could intervene in a lawsuit between state and federal governments over cleanup costs for an environmentally hazardous waste site under Superfund law (Comprehensive Environmental Response, Compensation, and Liability Act). The community group, Concerned Neighbors in Action (CNA), wanted to ensure that the clean-up was thorough enough to protect their health and property values. However, both lower courts denied CNA's request to participate as they did not have legal standing - they were neither directly responsible for causing pollution nor liable for cleaning it up. On appeal though, the Supreme Court held that CNA had met all requirements necessary to intervene: significant interest in litigation outcome; inadequate representation by existing parties; potential impairment of its ability to protect its interests if not allowed intervention; application is timely made. This decision expanded citizen participation rights within environmental lawsuits.

In the dissenting opinion for Stringfellow et al. v. Concerned Neighbors in Action et al., Justice Brennan, joined by Justices Marshall and Blackmun, argued that the majority's decision to deny standing to Concerned Neighbors in Action (CNIA) was a departure from established precedent regarding citizen suits under environmental laws. The dissent contended that CNIA had demonstrated sufficient injury-in-fact as required by Article III of the Constitution due to their members' use and enjoyment of areas affected by potential hazardous waste contamination from the Stringfellow Acid Pits site. They also disagreed with the majority's interpretation of "aggrieved" party status under section 113(f) of Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), asserting it should include parties who are adversely affected or aggrieved within its meaning after an administrative settlement has been reached but before cleanup begins.