They contend Congress should never have handed that power to others through so-called citizen suits that are part of environmental, campaign finance and certain other laws. Back in 2000, a Supreme Court opinion opened the door for that possibility. The critical issue for citizen suits is who—the government or private citizens—collects fines and has control. A person filing a citizen suit must tell the government ahead of time. It was the thirty-first citizen suit Tennessee Riverkeeper had filed under the Clean Water Act since 2010.