<em>"We're going to take for a ride, Ratchett. Some time soon. We're going to GET you, see?" </em>(1.6.85)
The notes sent to Ratchett suggest that his death was the result of revenge taken by the mob, but they were actually faked.
"How many wounds are there exactly?"
"I make it twelve. One or two are so light as to be practically scratches. On the other hand, at least three would be capable of causing death." (1.7.19-20)
The number twelve is a very important number for this novel. As Dr. Constantine reports, there are twelve wounds on Ratchett; there also happen to be twelve members on a jury. That seems to imply that this isn't a straightforward murder, but instead an attempt at a trial by jury. Apparently, Ratchett was found guilty.
"The question we have now to ask ourselves is this," he said. "Is this murder the work of some rival gang whom Cassetti had double-crossed in the past, or is it an act of private vengeance?" (1.18.20)
Poirot and his sidekicks must determine who is taking revenge on Ratchett. Are they dealing with killers who are also bad, or with people who are actually trying to do good?
"Excellent," said Poirot. "We can open our Court of Inquiry without more ado." (2.1.5)
Poirot uses the language of the courtroom, suggesting that he will act not only as detective, but also as a judge of sorts.
"If ever a man deserved what he got, Ratchett or Cassetti is the man. I'm rejoiced at his end. Such a man wasn't fit to live!" (2.2.13)
Though he was not convicted of any crime, everyone on the train agrees that Ratchett deserved to die. In this case, MacQueen is expressing that opinion. Is Ratchett's death justified?
"In fact, Colonel Arbuthnot, you prefer law and order to private vengeance?"
"Well, you can't go about having blood feuds and stabbing each other like Corsicans or the Mafia," said the Colonel. "Say what you like, trial by jury is a sound system." (2.8.89-90)
Colonel Arbuthnot's comments are a hint as to the solution of the murder: the twelve stabs come from twelve "jurors," so to speak.
"She is cold. She has not emotions. She would not stab a man; she would sue him in the law courts." (2.12.7)
Similarly, this reference to Miss Debenham (spoken by Dr. Constantine) is a hint as to the outcome of the case.
"You do not believe in doing your utmost to further the ends of justice?"
"In this case I consider that justice – strict justice – has been done." (3.5.38)
Princess Dragomiroff believes that by killing Ratchett, justice is served. Do you agree with her? Is it okay for ordinary citizens to take it upon themselves to act as a jury and executioners?
"I remembered a remark of Colonel Arbuthnot's about trial by jury. A jury is composed of twelve people – there were twelve passengers – Ratchett was stabbed twelve times." (3.9.58)
In case you missed it before, the link is spelled out for us.
"Ratchett had escaped justice in America. There was no question as to his guilt. I visualized a self-appointed jury of twelve people who condemned him to death and were forced by exigencies of the case to be their own executioners. And immediately, on that assumption, the whole case fell into beautiful shining order." (3.9.59)
Again, Poirot elaborates the metaphor.
"I would have stabbed that man twelve times willingly. It wasn't only that he was responsible for my daughter's death and her child's, and that of the other child who might have been alive and happy now. It was more than that. There had been other children before Daisy – there might be others in the future." (3.9.83)
Linda Arden admits that she would have taken on the sole role of executioner if she had to. Clearly she thinks of this as a case of justice, not revenge. Her motivation is preventing Ratchett from killing again, not simply getting back at him for murdering her granddaughter.
M. Bouc cleared his throat.
"In my opinion, M. Poirot," he said, "the first theory you put forward was the correct one ¬– decidedly so. I suggest that that is the solution we offer to the Yugo-Slavian police when they arrive." (3.9.89)