Earlier this week, the government revealed that a grand jury sitting in Washington, D.C., indicted a former Trump presidential campaign chairman and his former deputy and business partner for numerous felonies.

Both were accused of working as foreign agents and failing to report that status to the federal government, using shell corporations to launder income and obstruction of justice by lying to the federal government.

The financial crimes are alleged to have occurred from 2008 to 2014, and the obstruction charges from 2014 to 2017. At the same time it announced the above, the government revealed that a low-level former foreign policy adviser to the Trump campaign, George Papadopoulos, had pleaded guilty to lying to the FBI and become a government witness.

Does any of this relate to President Donald Trump? Here is the back story.

At the same time that Paul Manafort and his business partner Rick Gates were guiding the Trump campaign in the summer of 2016, Russian agents were manipulating American social media sites so as to arouse chaos in general and animosity toward Hillary Clinton in particular. The Department of Justice appointed former FBI Director Robert Mueller as independent counsel to determine whether any Americans had criminally helped the Russians.

The alleged crimes of Manafort and Gates appear to have nothing to do with Trump, nor have they any facial relationship to the Russians. So why were these two indicted by a grand jury hearing evidence about alleged American assistance to Russian interference with the 2016 presidential campaign. When prosecutors confront a complex series of potentially criminal events, they often do not know at the outset of their investigation where the evidence will lead them. Sometimes they come upon a person who they believe has knowledge of facts they seek and that person declines to speak with them. Such a refusal to speak to the government is perfectly lawful in America, yet it often triggers a prosecution of the potential witness so that prosecutors may squeeze him — not literally, of course — for evidence to which they believe he can lead them.