There are still a few questions that fans of The Godfather continue to debate, and one of the biggest is how Michael Corleone knew Carlo Rizzi was behind Sonny’s murder. The film offers no direct answer — Carlo only confesses just before his death. The novel doesn’t give an explicit answer either, but it offers just enough detail for readers to piece things together.
The short answer is that Michael didn’t know for sure until Carlo confessed. However, both the book and the film provide subtle clues suggesting that the Corleone family had long suspected Carlo’s involvement. And while these hints are more obvious in the book, the film does leave enough for a sharp-eyed viewer to draw their own conclusions.
Why Did Carlo Set Sonny Up?
Vito Corleone never approved of Carlo, which is why he gave him a living but never discussed family business with him
Carlo ran a Bookmaking station for the Corleone family but lost it during the Five Families War
Emilio Barzini approaches Carlo, who agrees to help lure Sonny to the ambush.
From the beginning of their relationship, Carlo saw Connie as a ticket to status, wealth, and power. However, Vito Corleone, disappointed that his only daughter had chosen an outsider, decided to keep Carlo at arm’s length. So, Carlo was given a living by running a Corleone-owned bookmaking company but was kept out of the family business.
However, due to the Five Families War, the Corleones were forced to close down some of its most profitable bookmaking stations, including Carlo’s. To cope, he took to drinking, sleeping around, and taking his anger out on Connie. After the Don’s attempted assassination, Sonny finds Connie covered in bruises, and despite her begging him not to intervene, beats Carlo half to death in the street and warns him that if he ever touched Connie again, he’d kill him.
So, when Barzini approaches him and offers him things the Corleone family refused him, he accepts. And, if there was anyone in the family he was willing to betray, it would be Sonny. He staged a fight with Connie, planting the bait with a phone call from one of his mistresses. Connie then confronted Carlo, who deliberately escalated the situation, beating her with his belt. Then, like clockwork, Connie calls Sonny. And Sonny, true to form, charged out the door in a blind rage and walked straight into Barzini’s ambush.
Michael Was Suspicious of Carlo for Years After Sonny’s Death
Neither the book nor the film has one definitive moment that suggests Michael knew Carlo was behind Sonny’s death.
Instead, it’s implied that Michael didn’t know for certain until Carlo confessed
The book and film do offer several hints to suggest that the Corleone family was suspicious of Carlo the moment Sonny was murdered
How Michael knew about Carlo setting Sonny up for his murder is one of the biggest questions fans still ask today. And, to answer the question, in short, he didn’t. But he and the Corleone family did have their suspicions. It’s easy to forget, whilst watching The Godfather, that the events of the film are spread across ten years. And, while Francis Ford Coppola’s two-part saga is faithful to its source material, there’s only so much that can be translated into a three-hour adaptation.
Several questions fans have had about The Godfather films are answered in Mario Puzo’s book. Or, at least, expanded on with enough detail to allow readers to come to their own conclusions. This includes Carlo’s involvement in Sonny’s murder. In the novel, after Sonny’s death, it’s made clear that the Corleones strongly suspect Carlo played a part, especially given how perfectly timed the trap was after his fight with Connie. Right after Sonny’s murder, Tom Hagen calls Carlo. An excerpt from the book reads.
That was the first indication in the book that the Corleone family had suspicions about Carlo’s involvement, and throughout the last half, several dropped lines further hint at this. Michael tells Kay that Carlo and Connie were nervous that the rest of the family blamed them for Sonny’s death, filling her in about the fight and phone call. Despite saying Carlo has since “straightened himself out” and now has an important role in the family business, Michael hesitates when asked if he blames Connie or Carlo. He says no for Connie, but his answer for Carlo is a little vaguer. Later on in the book, after Michael has Carlo killed, Hagen explains to Kay that Vito Corleone was aware of Carlo’s betrayal, but didn’t want to make his only daughter a widow. That’s why Michael waited until after his father’s death to kill Carlo, keeping him close in the family business to avoid suspicion in the meantime.
The film leaves out these smaller details, so it’s easy to understand how fans of the film, who’ve never read the book, would be confused by Michael’s sudden knowledge. But, like the book, the clues are all there, just not spelled out. Firstly, after Sonny beats Carlo for abusing Connie, Carlo was one of the few close to the family with both the motivation and means to set Sonny up. Secondly, – again this is something easy to miss unless you’ve read the book – towards the end of the film, Kay asks Michael to be godfather on behalf of Connie. When Michael exclaims that she can ask herself, Kay responds, “She’s afraid to.” This means that she’s afraid that the family will blame Carlo for Sonny.
Neither the book nor the film outright says “Carlo set Sonny up” before his confession in the end. But, it’s naturally assumed that Michael knows everything at this point – the phone call, the alleged setup, and Vito and Tom’s suspicions. When Michael finally confronts Carlo in the final act, he tells him they’re settling all family business, insists he won’t be harmed, but to not undermine his intelligence and tell him the truth. Believing he’s going to survive, and that Michael wouldn’t make his only sister a Widow, he confesses that Barzini approached him to set Sonny up. And that was the moment Michael knew it was Carlo.
The Godfather never shows the exact moment Michael puts it all together because there isn’t one. He doesn’t know for sure until Carlo confesses. However, what the film does show is Michael keeping Carlo close but powerless, Kay saying Connie is “afraid” of asking Michael directly, and Michael only confronting Carlo after all of the other enemies have been dealt with. It’s only after reading the novel that these small, seemingly insignificant moments in the film start to stand out.
Even 53 years on, The Godfather still has fans debating, questioning, and coming back for more. For those willing to dive deeper, Mario Puzo’s book offers far more than the films ever could. While the film stays remarkably true to the book in terms of characters and plot, certain moments—subtle but critical—become much clearer when you read the original source material.
