So I've long been curious about this topic. The legal basis of tyrannical states has long been of interest to me. The classic case is that of the Nazis (at risk of invoking Godwin's law!) We like to think of the Nazis as essentially evil thugs, but in truth as far as the law is concerned they conducted themselves in a similar manner to any state. Their treatment of the Jews, for instance, was not simply a matter of Nazis going out and treating Jewish people badly; they discussed policy, wrote and enacted laws concerning how people would be treated, established legal procedures, all that.

This is why the Nuremberg trials were so groundbreaking - the fact is that under German law, what the Nazis did was largely if not entirely legal. Hence the basis to try them for war crimes was not German law, but international law.

But in Star Wars, the Empire covers everything we see. And it is not defeated from without by an external enemy, but from within. (I should note, all I know of Star Wars is the movie universe. Maybe the books and such say differently.)

So there can be no equivalent of "international law" because the galaxy is one "nation".

So say I'm a Stormtrooper walking down the street, doing my thing. And somebody sees me and runs away. I shoot him in the back and he falls down dead. My question is, have I broken any law? Presumably my Stormtrooper officers will pat me on the back and say "well done", right? But is it the case that, like in Nazy Germany, Imperial law allows stormtroopers to oppress or even shoot people, or is it the case that my actions are still murder, it's just that the law is unenforced?

If it is the former, then when the Empire falls to the rebellion and the Republic is restored, what happens then? If the new Republic police arrest me, can I just say "Hey, under Imperial law I was allowed to shoot people. I did nothing wrong. Sure, you may have changed the law NOW to remove any such authority, but changes to the law are not retroactive - at the time, I was following the existing law so there is no basis to attest me."?

Of course if it's the latter, that the Empire just ignored the law, then the Republic would have a basis to charge me with murder. But that situation has interesting implications of its own. Because if it's true that the Empire just ignored the existing law, then the situation would really be pretty anarchic. Like, suppose I'm a real horrible Stormtrooper guy and one day I just start shooting civilians at random as I walk down the street. No reason, nothing but me feeling like having a good time. Do my trooper buddies try to stop me? Why would they, if nobody enforces the laws? Do they even bother having courts and police and prisons if the laws are openly ignored all the time anyway?

This is exactly why the Nazis took the approach that they did, by the way - because if you're not going to have laws and courts to rigorously apply them, the outcome is literally anarchy. Any given person will do whatever they feel is allowed, and will only be pulled up for it if those in authority happen to disagree with them. You can't have any consistency under such a situation, because the authority figure you're dealing with today might have a completely different idea of what's reasonable than the one you're dealing with tomorrow does. The primary function of law is to grant consistency, which leads to stability. Without consistency and stability a state really can't function at all, or at least can't do so remotely well.

Now there is some stuff in the movies to support the idea that both systems were in play in the films. We see in the prequels that the Republic senate votes to grant Palpatine emergency powers; he therefore has a legal basis to form the Empire. One can assume, then, that everything he does is actually legal because of this. So when Anakin killed all the kids in the third movie, he wasn't murdering anybody - Palpatine had the legal authority to order those deaths and Anakin had the legal authority to act as executioner.

We see in the original movie that the Senate remains in force up to that point, and thus presumably it remains the case that Palpatine's power as Emperor stems from their authorisation. However, Tarkin says this :

TARKIN : The Imperial Senate will no longer be of any concern to us. I've just received word that the Emperor has dissolved the council permanently. The last remnants of the Old Republic have been swept away.

TAGGE : That's impossible! How will the Emperor maintain control without the bureaucracy?

TARKIN : The regional governors now have direct control over territories. Fear will keep the local systems in line. Fear of this battle station.

So it seems to me that the Empire gives up any semblence of legal authority at this point, and decides to conduct itself purely as a terror state. Which, to my mind, means that it was on a path that would inevitably lead to collapse in short order, even if there was no rebellion at all. Because that kind of government just can't work.

Anybody have any thoughts on this topic?