At the heart of the early American court-martial was the convening authority, the military commander with the legal authority to convene such a proceeding. The Army and Navy of the period was not only quite small relative to today, they also existed in a world with limited communications bandwidth. Generals, Admirals, and (Navy) Captains received their general orders from the Commander-in-Chief and were delegated vast authority to otherwise act on their own pursuant to the Commander-in-Chief’s “intent.”
Courts-martial of the period were primarily the (sole) medium to imposing punishment and maintaining control over enlisted men. This is an important point to understand. A criminal proceeding in a regularly constituted court of competent jurisdiction is, at least in theory, intended to independently assess the facts of a case to determine whether the government has proven its case beyond a reasonable doubt and, if necessary, impose an appropriate sentence. Courts-martial by this period had a long history of being a creature of necessity outside regular law used to enforce conformity and discipline in an age before loyalty to a state, much less a constitution, while attenuating charges of arbitrary and capricious whims (which would not be the acts of an officer and a gentleman).
Under the conventional perception of courts-martial of this era, a panel of military officers heard the evidence and independently determined guilt. Likewise, this same panel independently determined the appropriate sentence. Courts-martial of the period had no maximum punishment tables nor sentencing guidelines. Sentences were determined, paraphrasing, “as a court-martial may direct.”
So, one would be fine to think the convening authority acted as an appellate authority over the independent determination of the court-martial panel.
The convening authority selected the panel of officers to determine guilt and adjudge a sentence. He also selected the prosecutor, who also spoke for the Accused. If the convening authority disagreed with a particular ruling by the panel, he could re-submit the issue for further review. Same goes for the sentence.
Oh, and he also rated each of the officers selected for the panel, meaning he was in control of their career.
As a further indication of a court-martial’s administrative hearing character, though there were no early rules of evidence or procedure, the early Articles specifically spelled out that the trial judge advocate was responsible for compiling the record of trial and forwarding it to the convening authority. He then had the authority to approve the findings and sentence, set them aside, or approve a lower sentence.
An additional copy was forwarded to the JAG Department in Washington, DC. At the time, the department had no authority to do anything to the approved findings and sentence. The most it could do was, upon review, provide recommendations to the convening authority to consider in the future. In fact, it was not until Brigadier General Samuel Ansell in the early 20th century that the JAG Department asserted Congress intended it to have jurisdiction over courts-martial.
But, that is hundreds of years away. In colonial times, the convening authority’s power was virtually absolute and he remained the only “appellate” authority in a court-martial. As you can probably imagine, this was abused, and Congress almost immediately stepped back in to require a bit more supervision.
More next time.
 Then, and now, there existed multiple types of courts-martial, differentiated by the type of punishment it was authorized to impose. The more serious the authorized punishment, the higher rank the convening authority needed to be.
 In a separate post I might venture a little more into officer courts-martial. While there are some notable cases, mostly an officer was just as likely to demand a trial by court-martial when “dishonored” as he was to face a court-martial for misconduct. And even when that happened, officers were loathe to convict one of their own.
 Also in a separate post, I will explore a bit more why this was so. For now, recruiting was different, military organization was different, enlisted men were different. It was just a different time and a different people, and a different need.