That would be a cogent argument, except that it has been established that the crimes a BBEG is guilty of are generally punishable by death in the OotS universe. Hence, avoiding lawful authority and executing a sentence that would be in line with that which would otherwise be handed out by lawful authority doesn't show disrespect for life any more than bringing an evildoer to trial to have a sentence executed would.
I wasn't talking about the oots universe specifically, but I suppose i should. Where do you get "the crimes a BBEG is guilty of are generally punishable by death in the OotS universe" from? Nale went to prison. Belkar wasn't murdered on the spot for killing that guard. In fact, I think in oots, location matters, and it matters quite a bit. I'm trying to think, but other than Belkar (and the war, obviously), I can't recall once that the party has killed a sentient being inside a town/city. Some times in the wilderness and ruins/dungeons, but they seem more keen to take enemies alive when in the midst of civilization. Why does this matter? Elan had Kubota on the Azurite's ship. For all purposes, this is just as much a society as Azure City was, and I'm sure they have laws they uphold. I'd be willing to bet that giving accused persons some sort of trial, like the law had it in Azure City, is one of those laws. That may be an important difference. Kubota could have been given to the rightful authorities, and V murdered him in an area with laws against that.
Your example is a complete non-sequitur. V determined that the person tied up had to be a BBEG, using metagame logic. In your example, the PC killed someone "in a murderous rage". The two aren't even remotely similar.
I wasn't comparing the events of oots to that issue, I was comparing your line of ethical argument, being stuck on the chaotic parts of the action and somehow thinking that because it's chaotic it's not also possibly evil. In both situations, both you and that player were basically arguing that because the murder was "chaotic" -- in his case random violence, in the strip's case not wanting to deal with legal proceedings -- that's the end of it. No consideration on the good/evil axis. That side note had nothing to do with the comic itself.
I think most people in this thread simply don't get why we have trials. A trial is not good in and of itself. However, in the real world we treat it as such because it is the only fair way we have come up with to reliably determine guilt and innocence and the level of culpability that should be assigned to the guilty. If we had magic mirrors that could view the past and see "the truth" we could dispense with trials. But we don't. So trials are seen as good - because they are the only known way we have of determining who has done "evil" and who has not.
But in the OotS universe, this is not true. V has outlined a perfectly valide metagame way to determine guilt and innocence, and in this case, the method has been 100% accurate. The only way you can say that V's act was evil is if you say that imposing the death penalty in the OotS universe after a trial is also evil.
It's not an entirely valid metagame reason. Being good isn't easy, and the good choice is often not the expedient, simple, or "fun" one. Just because V found killing Kubota to be more efficient does not make the act non-evil. If we could get rid of a major disease by simply murdering every single person with that disease, it's still evil even if it's more efficient than spending untold decades trying to find a cure as scores die from it anyway. Well, most people would call it evil, at least.
I'm not saying this one act made V evil, but (s)he did commit an evil act. And yes, a chaotic one, too.