I think I would define murder, as the premeditated intentional killing of a human being, with that decision made by the perpetrator himself.
I would not consider accidental deaths to be murder.
I would not consider deaths caused by war to be murder. Those deaths in my view would not be intentional taking of innocent life as decided on by a criminal perpetrator.
You pose an interesting question. I look forward to others responses to this.
Thank you for responding. Your definition is at least a good beginning!
I would want to distinguish between just killings and unjust killings in war. One cannot say that all killings in war are outside of the definition of murder. All expressions of the American military ethic — including, I think, the U.S.Army Field Manual -— make clear that some killings in war are unlawful.
Keep in mind that morally upright American military men used force and the threat of force to STOP other American men from massacring civilians at My Lai. Killing those unarmed villagers in the ditch was murder. Those who stopped the massacre were the true men of justice, upholding the American and Judeo-Christian ethic.