Michael McCormick was working on an electrical circuit when it exploded and seriously injured him. His employer got burned, too.
The Occupational Safety and Health Administration fined the company because McCormick wasn't using proper insulation and protective equipment. The company appealed, saying the explosion was caused by "unpreventable employee misconduct" because McCormick violated company safety policies and his supervisor's instructions.
But a court upheld a ruling by an administrative law judge that the company didn't do enough to enforce its safety program. The judge found that the supervisor left it to McCormick's discretion on how to proceed. Relying on the usually good judgment of an experienced worker may be reasonable, the judge said, but it violated federal regulations. (Massachusetts Electric Construction Co. v. Occupational Safety and Health Administration, No. 99-1600, 1st Cir., 2000)
Advice: You'd think establishing work rules and communicating them to employees is enough. It's not, even in the case of an employee who should have known better. To win on a defense of unpreventable employee misconduct, you must prove you diligently supervised employees and regularly enforced safety policies.
Tip: Regular safety meetings are a good way to reinforce key safety issues and avoid both injury and liability.