Drinking on the job hardly ever pays off and using any intoxicating substance at work can lead to the loss of workers' compensation benefits if the injury proves to be caused by such an activity. In the context of a claim petition, the employee bears the burden of proving that they sustained a work-related injury in the course and scope of employment. If an employer wants to assert the intoxication defense, it must plead this in its answer to the employee's claim petition. The Pennsylvania Workers' Compensation Act defines the intoxication defense as follows: "In cases where the injury or death is caused by intoxication, no compensation shall be paid if the injury or death would not have occurred but for the employee's intoxication, but the burden of proof of such fact shall be upon the employer." See 77 Pa. Stat. Ann. Section 431.