I'm not quite sure the alien race would be worthy to judge us. After all, the aliens are also mortal beings, they are not God. So what right do they have to judge over humanity? Are their reasons to exterminate us just, or just a sign of their lust of power maybe even worse than ours. In Dutch we say "Er is altijd een baas boven baas" (lit. There's always a boss above a boss) which means that no matter how extreme something is, it can always be topped (no matter how unlikely). Aliens even wanting to judge us can even be taken as a big arrogance on their side. So the entire trial would show them to be just as bad (or even worse) than we are no matter how you put it. I guess, I now insulted the supreme high alien court, but if they are really as fair as they claim to be, they would dismiss the entire trial with that kind of argumentation, and if they do not, they are not qualified for the job given to them, so we don't need to worry about a war to defend ourselves.
