Headscratchers / Murder on the Orient Express

• In one of the Poirot TV adaptations, an American investigator was in London searching for mob-connected fugitives. Could the FBI or a similar organization have gone to Yugoslavia to investigate the murder once word got out and start connecting the same dots Poirot did, thus making his help with the cover-up all for naught? Granted, once they discovered the victim's true identity, they probably would not have put much effort in.
  • Would it be necessary? There is an official explanation, offered by a famous detective, confirmed by a medical report, and a major criminal and asshole has been offed, sparing the costs of a manhunt and subsequent trial. The Feds (or possibly US Marshals - this troper is an European, so the US people would have a better grip on this) would be interested in catching Cassetti and bringing him to justice, once he's confirmed dead, then it's well, he cheated the hangman and that's all. Plus, after Poirot's denouement, even if there was any other investigation, the culprits would likely cover all the missed dots by then or get a better story. Plus, there is a matter of jurisdiction: would the US law enforcement be actively conducting an investigation in an European country that has a functional law enforcement of its own?
    • Cassetti was murdered outside the FBI jurisdiction. And while the U.S. authorities would are very firm about investigating U.S. citizens coming to violent death abroad, getting Yugoslavia to extradite twelve people, for the reason of "they killed the mobster before we could get to him and we're not even sure which one of them actually did it" is an effort they simply wouldn't be willing to put in. The bastard is dead, and let the Europeans bother about the details, would be the conclusion.
    • Also, would a Yugoslavian jury or even judge of the period have felt like condemmning the twelve to the full penalty of law because of the harm done to them and theirs? Or is my mental picture of interbellum Yugoslavia formed by the 'wild east' portrayal of both this novel and As the Wheel Turns / The Lady Vanishes? (Not to mention the fact that some metropolitan Yugoslavians looked down on the provinces as hicks.)
    • Whichever jurisdiction tried them, it would be difficult to get convictions. One has a diplomatic passport and would therefore be next to impossible to apprehend, and one is clearly physically unable to deliver a killing blow. The rest could plausibly be charged, but even assuming public pressure didn't lead to them being let go, assuming (as some adaptations show) he was drugged in addition to his usual sleeping medication, the best charge they could get would be indignity to a body. The killer would be whoever poisoned him, and good luck figuring out who that is.

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