Judicial Deference to Agency Decisions. Knox Creek Coal Corporation operates coal mines in West Virginia.The U.S. Department of Labor charged Knox's Tiller No. 1 Mine with "significant and substantial" (S&S) violations of the Federal Mine Safety and Health Act.According to the charges, inadequately sealed enclosures of electrical equipment in the mine created the potential for an explosion.The Mine Act designates a violation as S&S when it "could significantly and substantially contribute to the cause and effect of a coal or other mine safety or health hazard."

Challenging the S&S determination, Knox filed a suit against the Secretary of Labor.The secretary argued that "could" means "merely possible"--if there is a violation, the existence of a hazard is assumed.This position was consistent with agency and judicial precedent and the Mine Act's history and purpose.Knox argued that "could" requires proof of the likelihood of a hazard.

When does a court defer to an agency's interpretation of law?Do those circumstances exist in this case? Discuss.