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Special Counsel Robert Mueller has referred three investigations involving Washington insiders to federal prosecutors in Manhattan, apparently after determining the foreign lobbying cases fell outside of his mandate, CNN and The New York Times report. The three powerful lobbyists now being scrutinized by the U.S. Attorney's Office for the Southern District of New York — Tony Podesta of the Podesta Group, former Rep. Vin Weber (R-Minn.) at Mercury Public Affairs, and former Obama White House Counsel Gregory Craig at Skadden, Arps, Slate, Meagher & Flom — allegedly failed to register as foreign agents for work on behalf of Ukraine contracted through Paul Manafort, President Trump's former campaign chairman. Unlike Manafort, none of the three have been charged with any crimes, and its not clear the investigations will lead to any indictments.

Under the Foreign Agents Registration Act, "anyone who lobbies or conducts public relations on behalf of a foreign interest in the United States must register with the Justice Department," the Times explains. "The law carries stiff penalties, including up to five years in prison. But it had rarely been enforced, and thus widely ignored, until recently. Now, it appears to have become a weapon for prosecutors."

Podesta — the brother of Hillary Clinton's campaign chairman, John Podesta — and Weber were hired to advocate for Ukraine by the Brussels-based nonprofit European Center for a Modern Ukraine, controlled by Manafort. Their firms were each paid more than $1.1 million for the work, but they only registered with the Justice Department as foreign lobbyists retroactively, in 2017. The team led by Craig, who left Skadden in April, was hired directly by Ukraine's previous government.