The curious case of the alleged American "spy" detained in Russia

More peculiar details continue to come out about Paul Whelan, the former U.S. Marine arrested and charged with espionage while reportedly traveling to a wedding in Moscow last week.

Driving the news: Whelan, who is facing 20 years in a Russian prison, holds Canadian, British and Irish passports — a fact that threatens to drive a wedge between Russia and four Western countries that have now sought consular access. In 2006, Whelan was arrested for attempting to steal more than $10,000 of government money while on deployment in Iraq, the Washington Post reports. He was convicted and discharged for bad conduct in 2008.

• According to The Daily Beast, Whelan's lawyer Vladimir Zherebenkov is "a former Soviet government investigator who has never before tried an espionage case involving a foreign citizen."
• Zherebenkov told ABC News that Whelan intends to plead not guilty, but then said — unprompted — that the most likely outcome is a prisoner exchange. Security experts believe that prisoner could be Maria Butina, a confessed Russian agent who pleaded guilty to conspiracy charges last month, and that Zherebenkov was appointed by Russia’s domestic security agency to negotiate Butina's release.

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