Legal scholars draw distinctions between government regulation and adjudication in the courts. Regulation is the more direct way to mandate safe behavior. A regulatory commission requires what it considers safe, and forbids everything else, leaving individuals, corporations, and governments the choice of complying or facing punishment. The rules regulators establish determine how thick a retaining wall must be, how many parts per billion of a substance will be tolerated, or how far a car window may roll down. Failure to meet a safety standard is a violation, whether or not an accident results. Regulators and courts can force compliance with standards and procedures even if no harm has occurred.