to be a front man, to lend one's name for illegal or fraudulent activities
Descobriram que ele era laranja de um esquema de corrupção.
They found out he was a front man for a corruption scheme.
The origin of laranja ("orange") as slang for a fraud proxy is genuinely disputed — linguists say pinning it down with certainty is close to impossible.
Source: História do Mundo — laranjas.
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