Utah Code § 34-34-4

Any express or implied agreement, understanding or practice between any employer and any labor union, labor organization or any other type of association, whereby any person not a member of such union, organization or any other type of association shall be denied the right to work for an employer, or whereby membership in such labor union, labor organization or any other type of association is made a condition of employment or continuation of employment by such employer, or whereby any such union, organization or any other type of association acquires an employment monopoly in any enterprise or industry, is hereby declared to be an illegal combination or conspiracy and against public policy.