but let me add some light to murder.
If you follow the civil disobedience [http://en.wikipedia.org/wiki/Civil_Disobedience_(Thoreau)] set up by Thoreau you should only use it for what is morally right, but denied by law; so if you view killing someone morally right in a certain situation but the law says no, then you could call upon civil disobedience; in this case my answer, like the previous poster, would be "yes".
For example I view morally eating meat as a moral wrong, a form of murder; other people clearly do not - if I then had a moral that said that killing people who broke my moral code was right - I as such wouldn't mind such a law, but it wont work since too many people wont care very much for it, and continue to break it, bankrupting the law and making it pointless.
Normal human murder, especially murder committed by sane men and women who have reasoned it out, and done it for their own benefit (outside self defence) are for the normal human, moral monsters, especially if they have killed their children/parents or in general someone cute - and very much like you (a link to you strengthen the injustice and sense of a moral wrong).
Very few, hopefully none, can say that killing a person, outside of self defence, is morally right, and what is morals here? I like Kant, and Hume.
For the Kant The Categorical Imperative [http://en.wikipedia.org/wiki/Categorical_imperative] and the law of universality fits in - that is would it be ok if everyone did as me? well if it was ok for everyone to kill people for their benefit (outside self defence) or at random, we would soon be wiped of this rock! can't be good that.
Hume, and the utilitarians [http://en.wikipedia.org/wiki/Utilitarianism] are consequentialists and simply believe that the overall utility is what counts, that is does this act benefit the world or not? if not then don't - in general killing someone randomly does not benefit humanity, nor the world - though you could argue that it would be self defence for Gaea, and there would be fairly good defences against that - but as always the dogmas comes in and rock the boat - and do not doubt that people in war often have moral "rights" to do so in their mind - for moral it seems is not easily pinned down.
So why did I start with a no?
For you used the word murder, murder is a word that implies an immoral killing; thus I view the killing of animals for luxury purposes murder, an immoral act to me; while I do not view someone who has no choice but to become a cannibal to survive morally wrong at all (unless he was immoral to how he got to that sassy meat). Nor are war heroes in general considered murderers at all for example see Simo Häyhä [http://en.wikipedia.org/wiki/Simo_H%C3%A4yh%C3%A4].
So what is murder, and what is not?
Clarification: in my mind the very word murder says that it is morally wrong; most people don't view eating non-human meat as a moral wrong, thus they will use words like killed, put-down or slaughtered; in war, again, it's killed, not murdered - murder is a moral wrong, euthanasia [http://en.wikipedia.org/wiki/Euthanasia] and we do have people who kill their loved ones for mercy for various reasons today due to pain, and they view it as euthanasia, but in the law of most countries in the west it is viewed as murder - and I would hope that those who believe they have moral rights to do this dare follow the civil disobedience moral contract - and admit what they have done so that they can challenge the rules of today - for they if they do not view it as murder does not see a moral wrong with it.
So on abortion when someone say that abortion is murder, they don't mean abortion is death/killing/euthanasia but that it's morally wrong, an immoral killing - people pro abortions would not use the term murder, since they do not view it as morally wrong.Now consider the how much emotions the grey zone of morality concerning killing/murder cause - people are often angry at me for being a vegetarian, why? for they know I view them as immoral in this, and I do to some extent; yet the question of abortion, euthanasia and the right to go to war are the emotional turmoils of today, no wonder since we care so much about our own, and thus others lives.