The facts surrounding the indictment of former House speaker Dennis Hastert are vague and suggestive.  He is being charged with several currency violations and one count of lying to federal investigators. 

The currency violations are the result of withdrawals from several bank accounts by Hastert over a two-year period that exceeded the $10,000 limit on withdrawals that needed to be reported under the law.  Much of that cash apparently went to one individual in order to cover up "prior misconduct" by Hastert dating back to his time as a teacher and wrestling coach.

Washington Post:

In 2010, confronted about the “prior misconduct,” the former speaker agreed to pay $3.5 million to the person “to compensate for and conceal his prior misconduct against Individual A,” prosecutors alleged.

That person, whose identity was shielded by prosecutors, has known Hastert most of his or her life, growing up in Yorkville, the city next to Hastert’s home town of Plano, in the exurbs west of Chicago. Prosecutors said the actions “occurred years earlier” than the 2010 meeting that sparked the payments.

The investigation began in 2013, by the FBI and the Internal Revenue Service, which cited “possible structuring of currency transactions to avoid the reporting requirements.”

Neither Hastert nor his legal team responded to requests for comment on the charges.

Hastert, an easygoing Midwesterner by nature, had a public persona closely linked to his career as a wrestling coach, something he cited in late 2007 in his final speech on the House floor.

“When I entered politics, I never envisioned that this former teacher and wrestling coach from Kendall County, Illinois, would have the opportunity to lead the United States House of Representatives,” he said at the time.

In addition to the banking charges, Hastert faces a count for making “false, fictitious and fraudulent statements” to federal investigators during an interview last December in which he was questioned about the many cash withdrawals for less than $10,000, just under the amounts that would have triggered disclosure requirements.

According to the indictment, investigators asked Hastert — an almost 21-year veteran of Congress whose lobbying clients include major energy and tobacco firms — whether his withdrawals were prompted “because he did not feel safe with the banking system.”

“Yeah . . . I kept the cash,” the former speaker told the agents, according to the indictment. “That’s what I’m doing.”

Over five years, Hastert withdrew about $1.7 million in cash from his various bank accounts — at one point in 2014 delivering $100,000 a month to the person in question, the indictment alleged. About half of the cash was withdrawn illegally, prosecutors said.

You can fill in the blanks about what this indictment is saying between the lines.  A former student was blackmailing Hastert, or Hastert was offering to buy the silence of the former student.  Either way, he's toast.  As for what his "prior misconduct" involved, it had to have been terrible enough that Hastert virtually emptied his bank accounts paying the former student off.

The fact that Hastert didn't report the blackmail – if it was blackmail – also suggests something so horrible that the former speaker felt that exposing his misdeeds by going to authorities would be worse than paying the individual off. 

Running afoul of currency law comes with a stiff prison sentence, because the law was designed to catch drug dealers laundering their money.  Given the number of counts against him, if convicted, Hastert will be lucky to see the light of freedom before he dies of old age.