SDCL § 62-4-37: Injury or death due to willful misconduct of employee not compensable.

No compensation may be allowed for any injury or death due to the employee's willful misconduct, including intentional self-inflicted injury, intoxication, illegal use of any schedule I or schedule II drug, or willful failure or refusal to use a safety appliance furnished by the employer, or to perform a duty required by statute. The burden of proof under this section is on the defendant employer.