Called “citizen suit provisions,” those parts of the laws allow regular people and advocacy groups to sue companies they believe are violating the law. In fact, a majority of environmental cases are citizen suit cases. Now, in a legal filing, the Trump administration is saying citizens should not be allowed to enforce environmental laws. Citizen suits often ask the courts to order a stop to the polluting activity, payments for reducing or cleaning up the harm done, and civil penalties paid to the government. But if the government has already begun an enforcement action or is actively prosecuting the violator, a citizen suit cannot proceed.