See you could understand that if someone took their own chips back the police would find it difficult because gambling debts are unenforceable (ianal) and the chips weren't someone else's yet (I doubt the pot is a legal entity with ownership rights), but when they took other people's chips from the pot then it sounds like a different matter to me.
Its all a bit confusing, Common sense would dicate that the pot is either the property of the casino until it is awarded to the winning player, or its held on trust by the casino for the winning player, it gets complicated i.e. if its the property of the casino, then they are in effect refusing to pay a winning bet, if its held on trust for the winning player then legally they are not under an obligation to pay the winning hand or so i think

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