I would think that this would be commercial misappropriation of likeness. (http://itlaw.wikia.com/wiki/Commercial_misappropriation) I guess that the USPS being sort-of a part of the US federal government might get them an out, and I'd guess that no federal judge in the US would find in Snowden's favor lest he, too, be deemed a traitor. Procedural hurdles could be thrown up, such as making him appear in court in person, and of course he'd be arrested before he got that far. And even if Snowden did somehow win a judgement he'd find it impossible to collect. Short answer, anyone in the US wanting to make money off of Snowden can likely get away with it.

 

(been to law school, blah blah, not a lawyer, blah blah)

 

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Neca eos omnes. Deus suos agnoscet. -- Arnaud-Amaury, 1209