Donald Trump the Megathread part II - Mod Warning updated in OP 12/2/26

What was known at the time?

There seems to be some idea that this "presumption of lawfulness" is unique to the military, it is not. It is the basis upon which all laws and executive functions have happened in the US since Day 1. Until a rule or process is challenged in the courts, there is nothing legally stopping it from being enforced.

Indeed, the military side of it has an additional protection in that the process requires oversight. At a trivial end of the scale, if a traffic warden decides to refuse to carry out the instruction to mark car tyres with chalk, which is standard practice for departments around the country, and is fired for doing so, then it becomes an administrative matter for the department, the union and arbitrators. And the chances are (s)he would lose and the event probably wouldn't go beyond page 3 of the local paper: The conduct is common and generally uncontroversial, and there is no mandatory trigger for a judge to have to rule that "yes, as it happens, that is unconstitutional. Surprise!" (Sixth Circuit, if you're curious). There is no legal safety net for the city employee.

Should a soldier refuse to carry out an order, let's say an MP enforcing parking restrictions on base, however, that becomes a criminal case under the UCMJ (or state equivalents). In order for a conviction to happen, a judge must assess that the order given was lawful (Or in the case of acquittal, unlawful). Without that assessment, punishment cannot happen. Administrative retaliation in lieu of court martial itself is subject to review under Art 132 or through the Inspector General's office.

Nothing illegal about it. The US didn't have common rules of engagement before the 1950s. The whole thing didn't become officially formalised in the military until the implementation of Standing RoE in 1994. Put simply, they are not legally required, the US managed to fight two world wars without them.

ROEs add to, but cannot detract from, the laws of armed conflict. They are emplaced because of operational or political benefit to be obtained from following them. Even if every RoE in the military was rescinded (Which Hegseth didn't actually say he would do, but let's assume), there is still an onus upon all soldiers to follow the laws of war.

Although Nuremberg principles are commonly misapplied in discussion of miltary law, something approximating "common sense" is actually the standard used in the US miltary justice system. The actual verbiage is "if a person of reasonable sense and understanding would have known".

The hurdle is the word "known" which is a high bar in legally unclear and controversial scenarios.