In the case of Eastern Associated Coal Corporation v. United Mine Workers of America, District 17, et al., in 2000, the Supreme Court ruled on whether a labor arbitration award that reinstated an employee who had twice tested positive for marijuana use was enforceable under public policy considerations. The court held that while there is a clear public policy against drug use in safety-sensitive industries such as trucking (the employee's job involved driving large vehicles), this does not necessarily mean every discharge related to drug use must be upheld. It found that arbitrators should have some leeway to consider mitigating circumstances and other factors when deciding if termination is appropriate punishment for misconduct. Therefore, it concluded that federal courts cannot refuse to enforce an arbitration award simply because they disagree with its interpretation or application of underlying law or policies unless the award itself violates explicit public policy.

In the dissenting opinion for Eastern Associated Coal Corporation v. United Mine Workers of America, District 17, et al., Justice Scalia disagreed with the majority's decision to uphold an arbitrator's ruling that reinstated a truck driver who had twice tested positive for marijuana use. He argued that public policy should override any collective bargaining agreement in this case because allowing someone under the influence of drugs to operate heavy machinery poses a significant risk to public safety. Furthermore, he contended that it was not within an arbitrator’s purview to decide matters of public policy and thus their decision should be overturned by courts when they conflict with such policies. The justice also expressed concern about setting a precedent where arbitration decisions could supersede federal law or regulations aimed at ensuring workplace safety.