Replace officer with "anyone" and you'll see your answer. Surely, you're not saying that I or anyone that doesn't have a badge can walk into a building, demand that someone do something, and when they refuse, shoot them because they moved their arm, which may or may not have held a weapon, right?
Nope. But the law covers that. Commands from LE aren't the same under the law as a command from you or me.
Some jurisdictions add the word "lawful" command, but any command an LEO gives, one may assume they believe is a lawful one, and during the resulting moments thereafter is not a particularly good time to attempt to argue it with them.
Some jurisdictions don't even add the word lawful.
Usually the command must be preceded by the LEO identifying themselves as LEO, and maybe some other rules about reasonable suspicion or what have you, it's not consistent anywhere.
If you do something stupid and survive it, unless you have a pile of credible witnesses who will testify that they didn't identify themselves as LE, or didn't follow one of the other jurisdictional rules -- your word against theirs won't be enough in any court before any judge worth their legal salt.
Once someone identifies themselves as LEO, the rules for following instructions, change.
The biggest problem this the law creates, and is backed up by **** poor training tactics, is the Officer who just starts yelling incoherently upon entering any particular space with no regard for intelligibility, hearing disabilities, what have you. How many videos have you watched where some doofus cop is yelling so incoherently and with multiple phrases or such an awful accent or whatever, where even listening through a mic on their person, you know you'd never be able to figure out that they were LEO or what the hell they're even saying, if you were there?
Of course, in court, their recollection of their behavior is going to be that they gave an aggressive but intelligible announcement as good as the White Zone guy in Airplane, and the acoustics of the room were pristine like a sound recording booth.
The poor training tactic I mentioned is the popular training that an Officer must yell and maintain "Alpha Dog" status as the only possible tactical solution to controlling a situation.
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