The two tier Foreign Agents Registration Act:

Lee Smith:

...

It is because FARA has been so rarely enforced in the past that many lobbyists wonder whether the point of the Mueller prosecutions is to encourage compliance -- or, instead, to turn a statute designed to encourage transparency into a prosecutorial instrument used against political adversaries.

“The test case,” said one lobbyist, “is Tony Podesta, and whether or not he’ll be charged for doing what Manafort did.”

Podesta worked with Manafort on the same public relations campaign for a Ukrainian political party that Mueller used to bring his FARA charge against the former Trump adviser. After Manafort’s arrest, Podesta dissolved his firm and was reportedly under scrutiny for possible FARA violations. Some reporting says Mueller offered Podesta immunity for testifying against Manafort. Elsewhere it's reported that he has referred the case to federal prosecutors in New York. The status of any allegation or possible probe remains unclear, and will ultimately depend on prosecutorial discretion.

For now, it looks like Podesta who did basically the same thing as Manafort is not being prosecuted.  It helps to be a Democrat when it comes to enforcement of this law.  It looks like the FARA statute has become a tool of prosecutorial extortion against people who worked on the Trump campaign even though their activity as "foreign agents" had nothing to do with Trump or the campaign.  It looks like a handy tool for Mueller's extortion racket.