I haven't read nearly all the letters on Heather's column, so perhaps what I'm about to say isn't original.

Maybe it's because I still really want to like Tony, but I didn't assume he actually murdered Christopher. It seemed as if Tony thought, or at least justified, his actions as a mercy killing. His reactions for the remainder of the episode are his way of dealing with a horrible decision--horrible because it was misplaced, not because it was wrong or immoral.

Much of the more gruesome violence on the Sopranos has been punctuated by short cuts, closeups, and odd camera angles of the carnage. There was a short cut that indicated to me Christopher's wounds looked mortal, or that was how Tony saw them. In this light, and in the context of Christopher's apparent losing battle with chemical dependency, Tony acted out of a sense of decency and honor, as he sees those concepts.

There is a scene later in the episode when someone laments that Christopher's injuries weren't necessarily mortal, and it was a shame he couldn't have held on. Tony's look could have meant that he felt an inner horror about his actions, that maybe he acted impulsively and unnecessarily. Shortly after this scene Tony darts out to Vegas.

Of course, the writing and Gandofini's acting brilliantly leave many possible interpretations. Was Tony's facial reaction in that scene mentioned above expressing guilt that he acted impulsively, or a reminder that he was, in fact, responsible for Christopher's death, guilty of his murder? More than likely, Tony's actions in the car were a mixture of mercy, vengeance, and business as usual.

Does anybody else think Tony's actions don't amount to murder, or that there is some ambiguity there? I'll watch again and reevaluate my interpretation.