(A) Parties may, of their own volition, file briefs with the bureau or commission on legal questions presented in claims.
(B) The bureau or commission may require parties to file briefs on legal questions presented in claims. The hearing officer shall fix a time certain for the filing of such briefs allowing a reasonable time for preparation.
(C) In either instance, the submitted briefs shall be legibly typewritten on paper not exceeding eight and one-half inches by eleven inches in size and filed without a protective cover. The party filing a brief shall furnish a copy to the opposite party at the time that the brief is filed with the bureau or the commission. If the brief is directed to a matter before the bureau, the brief shall be filed with the bureau. If the brief is directed to a matter before the commission, the brief shall be filed with the commission.