The new Mil. R. Evid. may not apply to any offense committed prior to it’s effective date? Is there an argument that application to an offense prior to the effective date violates the ex-post facto clause. See Calder v. Bull, 100 U.S. 1 (1798).
Article I, section 9 of the United States Constitution states in relevant part that “[n]o Bill of Attainder or ex post facto Law shall be passed,” and, in its opinion in Calder v. Bull, the Supreme Court recognized four types of laws that cannot be applied retroactively consistent with this Ex Post Facto Clause:
1st. Every law that makes an action done before the passing of the law, and which was innocent when done, criminal; and punishes such action. 2d. Every law that aggravates a crime, or makes it greater than it was, when committed. 3d. Every law that changes the punishment, and inflicts a greater punishment, than the law annexed to the crime, when committed. 4th. Every law that alters the legal rules of evidence, and receives less, or different, testimony, than the law required at the time of the commission of the offence, in order to convict the offender.
Here is Prof. Colin Miller TG’s blog on the retroactive application of FRE 413-414.