The city said a 2011 court decision made the protections illegal, but the bus workers' union said the ruling didn't apply to the routes under dispute.

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But having Americans on board the bus made it easy for police to either assume the Maldonados were the smugglers, or to target them for a bribe.

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In theory, some of those loopholes were understandable, but in practice they sometimes made it possible for millionaires to pay nothing, while a bus driver was paying 10% of his salary, and that's crazy.

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