Article 62 authorizes interlocutory appeals by the prosecution in a court-martial in various situations, including of:
An order or ruling which excludes evidence that is substantial proof of a fact material in the proceeding.
Art. 62(a)(1)(B). It’s a relatively new provision in the Code, having been added by the Military Justice Act of 1983, Pub. L. No. 98-209 (with additional grounds for appeal added in 1996).
Rule for Courts-Martial 908 details procedural steps for such an appeal, but it does not define the term (or perhaps terms) substantial proof of a fact material in the proceeding, leaving the matter up to the appellate court acting on the appeal.
The Judge Advocate General of the Army has a problem with that:
No. 17-0408/AR. United States, Appellant v. Erik P. Jacobsen, Appellee. CCA 20160768. Notice is hereby given that a certificate for review of the decision of the United States Army Court of Criminal Appeals on appeal by the United States under Article 62, UCMJ, and a supporting brief were filed under Rule 22, together with a motion to stay trial proceedings on this date on the following issue:
WHETHER THE TRIAL COUNSEL’S CERTIFICATION THAT EVIDENCE IS “SUBSTANTIAL PROOF OF A FACT MATERIAL IN THE PROCEEDING” IS CONCLUSIVE FOR PURPOSES OF ESTABLISHING APPELLATE JURISDICTION UNDER ARTICLE 62(a)(1)(B), UNIFORM CODE OF MILITARY JUSTICE.
Appellee will file an answer under Rule 22(b) on or before May 25, 2017.
I don’t see an opinion on the Army CCA’s website. Update: a reader forwarded the CCA’s order. It’s available here. The order states, in part:
Contrary to appellant’s claim, the military judge did not issue “[a]n order or ruling which excludes evidence that is substantial proof of a fact material in the proceeding.” UCMJ art. 62(a)(l)(B) (emphasis added). Although Congress intended to provide military prosecutors, to the extent practicable, with the same rights of appeal afforded to federal civilian prosecutors in 18 U.S.C. § 3731 (i.e., the right to appeal trial rulings dismissing charges or excluding substantive evidence), the jurisdictional language codified by Congress in Article 62, UCMJ, differs from 18 U.S.C. § 3731. See United States v. Lopez de Victoria, 66 M.J. 67, 68-71 (C.A.A.F. 2008) (explaining the general intent of Congress in enacting Article 62, UCMJ).
Specifically, the plain language of 18 U.S.C. § 3731 confers appellate jurisdiction over trial orders suppressing evidence, only conditioned upon timely certification from the United States attorney. United States v. Grace, 526 F.3d 499, 505-06 (9th Cir. 2008) (en bane). In contrast, the plain language of Article 62(a)(l), UCMJ, confers appellate jurisdiction for orders or rulings that actually meet specified criteria. Although Article 62(a)(2), UCMJ, contains similar timeliness and certification requirements to 18 U.S.C. § 3731, these requirements are listed separate and apart from the jurisdictional basis. Essentially, 18 U.S.C. § 3731 vests the determination of the materiality of the excluded evidence solely with the United States attorney; in this important respect, Article 62, UCMJ, is not analogous. When Congress intends to confer the right to appeal based solely on the certification of a specified officer, it is perfectly capable of making that intention clear in statutory language. Compare 18 U.S.C. § 3731, and Article 67(a)(2), UCMJ, with Article 62(a), UCMJ.