Pretrial, trial and posttrial procedures, including modes of proof, for cases before courts-martial arising under this Code and for courts of inquiry, may be prescribed by the Governor or the Adjutant General by regulations, or as otherwise provided by law. The regulations prescribed under this section must apply the principles of law and the rules of evidence generally recognized in military criminal cases in the courts of the Armed Forces of the United States and must not be contrary to or inconsistent with this Code.