It occured to me, why does Mike insist on knowing this before he has Carlo killed? Both Tattaglia and Barzini are already dead, and surely Carlo's answer will result in no change in his punishment. Mike's father is already dead so its not like he can go and tell him he was right.

So why? What is the point of making Carlo admit it was Barzini before he is killed?

By making Carlo admit that it was Barzini, Mike made Carlo confess to setting up Sonny.

Didn't really matter if Carlo had said it was Barzini or Tattaglia. Just by him saying to Mike that it was one of them, Carlo is admitting that HE was involved in setting up Sonny without really saying that he had set up Sonny.

By his telling Mike that it was Barzini, it was an admission of guilt on his own part.


Don Cardi

It is kind of weird by Michael to ask him that question, hoever Don Cardi's explanation is good enough to answer why.

By Mike asking that question it tells me that Mike was not 100% sure that Carlo was the one who set Sonny up. Making Carlo answer that question was his (Mike's ) way of knowing for sure.


Don Cardi

In the novel, I believe it is Tom Hagen who is surprised that Michael asked the question as well. He felt that by asking, Michael was admitting that he had a problem with executing Carlo, that he was unsure, and that the question itself was a sign of weakness.

It seems a bit weird. But I believe it was a power trip on Michael's part. Of course it didn't matter who approached Carlo--both Dons were dead and Carlo was plainly guilty. And in any event, Vito had earlier concluded that "it was Barzini all along." Surely he would have told that to Michael.
In the film, Carlo at first denies complicity. But watch Michael's demeanor: he's as grim as the Grim Reaper, but there's a touch of swagger in him (more evident a bit later, when you see him walking without his coat in the Mall). The swagger comes from his having pulled off the Great Massacre of 1955. So he presses his advantage by making Carlo confess. Sure, he knows Carlo is guilty beyond reasonable doubt. But he wants to further humiliate Carlo by making him admit both his guilt and his lie. Then, to twist the knife, Michael tells his own lie: he tells Carlo he's giving him a pass, only to have Clemenza kill him.
From Michael's viewpoint: the end of a perfect day.

Do you really think so Turnbull? I just don't see it that way. I've always felt that Mike was unsure, and he needed to know for sure. What's also made me feel this way is what SB said about the novel. Tom even took it as a sign of weekness on Mike's part. This indicates to me that Michael must have shared his doubts with Tom beforehand.

Now you've gone and FORCED me to watch GF again and pay close attention to that scene.


Don Cardi

"Unsure" is the conclusion Tom came to in the novel. But I think Michael's demeanor in the film is anything but unsure.

To elaborate on what Sicilian Babe said about the scene in the novel, Puzo writes that Tom and Rocco were both thinking that

Michael was still not that confident of his right, still feared being unjust, still worried about that fraction of an uncertainty that only a confesion by Carlo Rizzi could erase.

I think that given Michael's limited level of experience as Don, and considering that the events of this day marked his first major "play" in that role, it's not unreasonable to assume that he wanted to make sure that everything was "exactly right."

As far as the "Barzini or Tattaglia" question goes, I think it was just an example of a small loose end that Michael wished to tie up.

At that point, there was no answer that Carlo could have given that would have changed his fate.

All interesting analysis. It does seem like Michael is just getting some sort of cruel pleasure by watching Carlo squirm, break down, confess, be relieved in his supposed safety, and then be killed.

I think I have to agree with DC on the side of uncertainty. I think Michael was 99.9% sure that Carlo fingered Sonny, but unlike the Great Massacre, Carlo was a member of the family(Corleone not mob). Even though he was just an in-law, as Connie's husband and his death would cause her suffering. Michael knew he had to kill Carlo if he was a traitor, but if was going to put his own sister through the pain, he needed to be absolutely 100% sure that Carlo was guilty. It's easy to see Michael as the cold-hearted killer from GF II and not even think twice about whether he would kill a family member, but I don't think he had reached that stage yet when the Tattaglia or Barzini scene takes place in GF I.

Is there any information in the book on how Michael starts to suspect Carlo? Does he just use his cunning, or does the book mention something specific that causes Michael to start suspecting him?

Ill go with DC on this one too. I think Michael was almost sure, but he needed that confessioin (in front of witnesses) to seal it. This way he always had Tom to protect him from other family members who may have thought this act beyond the pale. There is an interesting quote at the end of the movie when Connie comes in screaming at Michael. She says he always blamed Carlo for Sonny and that "everyone did." So this means the family had a good idea that it was Carlo. If you think about it, Carlo was not the sharpest knife in the drawer, and the way he acted at Sonny's funeral and around the family after Sonny's death must have given him away.