If you had a workers compensation claim, and the employer is self-insured for that, then it's not at all illegal.  Part of what keeps the workers compensation system affordable is exactly this type of lien, when benefits have been paid but there's a third party with substantial fault.  Usually, it's an insurance company that has the lien, after paying the compensation benefits, but some larger employers can qualify as self-insured.This isn't really unfair at all.  Your lawsuit against the DUI driver will get a verdict or settlement that isn't any different than it would be if it had happened while you weren't on the job and got the same injuries.  The lien just prevents you from collecting double, at the expense of the workers compensation system.