It is unlawful for a peace officer to be employed within the State on a contingent basis upon which he receives any share of fines collected by him or through his efforts as compensation. A peace officer accepting employment on a contingent basis or receiving or accepting any part of the fines collected by him or through his efforts as compensation is guilty of a misdemeanor and, upon conviction, must be fined in the discretion of the court or imprisoned not more than three years.