Was Moses a murderer?

11 One day, when Moses had grown up, he went out to his people and looked on their burdens, and he saw an Egyptian beating a Hebrew, one of his people. 12 He looked this way and that, and seeing no one, he struck down the Egyptian and hid him in the sand. 13 When he went out the next day, behold, two Hebrews were struggling together. And he said to the man in the wrong, “Why do you strike your companion?” 14 He answered, “Who made you a prince and a judge over us? Do you mean to kill me as you killed the Egyptian?” Then Moses was afraid, and thought, “Surely the thing is known.” 15 When Pharaoh heard of it, he sought to kill Moses. But Moses fled from Pharaoh and stayed in the land of Midian. And he sat down by a well.

Most commentators are very judgmental about this episode. They accuse Moses of murder. They reprove him for murder. But does that reflect the narrative viewpoint, or is that a case of judging the incident by their own scruples? 

i) The context is similar to Exod 5:14. An Egyptian slavedriver beating or punishing a Hebrew slave. 

ii) Some commentators assume Moses is avenging the assault. That he waited until it was over with, followed the slavedriver, and killed him in an act of premeditated vigilante justice. 

Although that's possible, the text doesn't say that. It's at least as likely that he intervened during the assault, to protect the battered slave from further injury. We wouldn't automatically classify as murder defending someone who's being assault.  

Moreover, that doesn't imply intent to kill. As most, one might be prepared to use lethal force, if necessary. Again, we wouldn't automatically classify that as murder. Indeed, we naturally view that as admirable. Courageous. Putting yourself in harm's way to protect someone else from harm at the hands of a dangerous assailant. 

iii) Why did Moses check to see if the coast was clear before decided to intervene? It's possible that he was hoping someone else would intervene, but that's unlikely. Who else would intervene in a situation like this? An Egyptian wouldn't intervene to protect a Hebrew slave from a beating by an Egyptian slavedriver. And another Hebrew wouldn't dare interfere.

Moses knew he was taking a risk. His action would be viewed as treasonous by Egyptian authorities. He's not Egyptian. By intervening, he's shows where his true loyalties lie. 

That's also why he tries to cover-up the crime. Not from a guilty conscience, but because he rightly fears the legal consequences if his action is discovered. 

No doubt his intervention was a snap judgment. Perhaps he felt the assault was life-threatening. Or perhaps he was just incensed by the vicious brutality. 

Kaiser makes the odd comment that "the very impulse leads Moses to avenge wrongdoing apart from due process." But aside from the questionable assumption that Moses was avenging the misdeed, there was no legal remedy available to a Hebrew slave. It's not as if the Egyptian authorities were going to side with a Hebrew slave. From their perspective, the Egyptian slavedriver was just doing his job. And even if the beating were fatal, who cares about one more dead Hebrew slave? 

iv) However, this is a case in which a good intentions get you into trouble. Instead of keeping mum, the slave told his friends and family who came to his aid. Or maybe he ratted him out to shift blame.