(1) This Decree shall apply in every action, whether civil or criminal, and as provided in section 87 relating to privileges.

(2) In applying this Decree, and in particular in determining whether and to what extent to exercise its power under section 8, the court shall have special regard to the fair application of this Decree in respect of a party not represented by a lawyer.

(3) Any rule of law which provides that acts in derogation of the common law shall be narrowly construed shall have no application to this Decree.

(4) This Decree shall be interpreted and applied so as to achieve a consistent law of evidence and the most just, expeditious and least costly administration of the law.