The Informant Turned Defendant Who Took Aim at the Bidens

Alexander Smirnov was, in many ways, the archetype of an informant operating in the shadowlands of the former Soviet Union — a profiteer, fixer and gossip who promoted his ability to make sense of a confusing landscape to American law enforcement agencies.

For more than a decade, he played a double game, giving the F.B.I. tantalizing visibility into a cast of oligarchs and public officials while offering himself as a consultant, with a hard-to-define skill set, to some of the same people he was keeping tabs on.

Then he stepped over the line.

In 2020, Mr. Smirnov told his F.B.I. handler what prosecutors say was a brazen lie — that the oligarch owner of the Ukrainian energy company Burisma had arranged to pay $5 million bribes to both President Biden and his son Hunter. The explosive claim was leaked to Republicans, who made Mr. Smirnov’s allegations a centerpiece of their now-stalled effort to impeach President Biden, apparently without verifying the allegation.

Last week, Mr. Smirnov, 43, was indicted on charges that he lied to investigators about the Bidens. He was arrested as he was preparing to leave for what prosecutors called “a monthslong, multicountry foreign trip” during which he claimed to have plans to meet with contacts from multiple foreign intelligence agencies.

In court filings, prosecutors working for David C. Weiss, the special counsel investigating Hunter Biden, described Mr. Smirnov as a serial liar who could not even be trusted to describe honestly his own occupation or account for his finances.

Congressional Democrats predicted that the indictment would kill the impeachment push. Lawyers for Hunter Biden seized on it to try to undermine the tax and gun cases Mr. Weiss has brought against him. In a court filing, they contended that Mr. Smirnov’s false claims “infected” the cases, and suggested, without providing evidence, that prosecutors reneged on a plea deal last summer because they had followed “Mr. Smirnov down his rabbit hole of lies.”