I don’t know any more about the Shahram Amiri case than what was in the newspapers, but I have had a personal experience that may provide a precedent.
I was the American Consul in Tabriz from summer 1963 till summer 1965, and my first winter there was the worst on record, with massive snows and extreme cold. We were almost completely cut off from Tehran; for a while we were reduced to the antique device of the one time pad. Our little staff was going stir crazy, when our Branch PAO Tom Dowling electrified us with word that a genuine Soviet defector had come in out of the cold to his office. He said he was a Bulgarian and had worked in a Soviet nuclear establishment outside Sofia. The problem was language; he spoke Bulgarian and Russian and we didn’t. Bill Hallman, our Vice Consul and Farsi language officer, took the defector over and tried to elicit more info from him. Over several grueling and frustrating days the defector managed to eke out some plausible details of his escape from behind the Iron Curtain and his subsequent migration via eastern Turkey across the border to Tabriz. Meanwhile I was using the one time pad, almost equally unsatisfactory as a means of communication, to persuade Tehran to send us someone who could speak Bulgarian or at least Russian, and could take this character off our hands. No dice. Finally, as I was about to send a real rocket to my masters in the Embassy, Hallman came to me and said forget it Carl, the guy’s a phony. Bill had finally broken the wretch down: after several days of intense interrogation it turned out he spoke pretty good Farsi after all, indeed he was a native of Tabriz who had hung out at the bus terminal soaking up data about routes through Turkey from the transient drivers. He also had hung out enough at our library to decide he wouldn’t mind a free trip to our country, and this is how he decided to go about it.
Is it possible Amiri decided to parlay a distant view of the Iranian nuclear establishment into a free pass to the USA, and succeeded where my man failed because the market for what he claimed to offer was more propitious? and then when he realized how far he was getting over his head, he changed his mind and beat it back home?
I’m sure it’s more complicated than that, but lest we forget, the Farsi culture values the complex lie, as explained in loving detail in Morier’s classic “The Adventures of Hajji Baba of Isfahan.”