The indictment of Dennis Hastert, the former House speaker, on charges that he tried to conceal cash withdrawals to keep "prior misconduct" secret stunned some political allies and observers.
Republicans elevated Hastert from obscurity when they gave him the job in 1999, after Rep. Newt Gingrich resigned under pressure and his would-be replacement, Rep. Bob Livingston of Louisiana, resigned his own seat after admitting an affair.
"Hastert got the job because he was supposed to be clean as a whistle," said Sean Theriault, a professor in the Department of Government of the University of Texas at Austin. "In the aftermath of Gingrich and then the Livingston fiasco, the Republicans turned to Hastert because he was full of integrity."
By the time Democrat Nancy Pelosi took the gavel in 2007, Hastert had become the longest-serving Republican speaker in American history.
The indictment does not specify the alleged "prior misconduct" or when it supposedly occurred, but it mentions on its first page that Hastert was a high school teacher and coach in Yorkville, Illinois, from 1965 to 1981.
Hastert, 73, was charged with one count each of structuring currency transactions to evade currency transaction reports and making a false statement to the FBI.
He was accused of withdrawing $952,000 and paying an unidentified person in Yorkville to "compensate for and conceal his prior misconduct" against that person. He was accused of structuring the withdrawals to evade banking reporting regulations.
Hastert was allowed to remain free on his own recognizance, according to a court document. Bail was set at $4,500.
"I am speechless. He is my friend, has been my friend [and] will always be my friend," Illinois House Republican Leader Tom Cross told NBC Chicago.
POLITICO reported that rumors about Hastert's legal troubles had been circulating around Capitol Hill in recent weeks. In an interview with the publication last week, Hastert denied he had issues with the IRS and denied that he was about to be indicted.
Hastert was born in Aurora, Illinois, west of Chicago, and was a teacher and coach in Yorkville before being elected to the Illinois state House of Representatives and then to Congress in 1986.
As speaker, he pushed President George W. Bush's legislative agenda, helping pass a massive tax cut and expanding Medicare prescription drug benefits.
He is credited with the so-called Hastert Rule, which holds that no piece of legislation should reach the floor unless a "majority of the majority" supports it — although Theriault said former Rep. Tom DeLay acted as the party enforcer.
Hastert was criticized in 2006 over his handling of a scandal involving salacious emails and instant messages sent by now former Rep. Mark Foley to pages, and there were calls for Hastert to resign. Democrats seized control in the elections of that year, and Hastert resigned from Congress in 2007.
His leadership of the House was vastly different from Gingrich's. Hastert preferred to play a behind-the scenes role in getting legislation passed, said John J. Pitney, professor of American politics at Claremont McKenna College in Claremont, California.
But because Hastert became speaker during President Bill Clinton’s lame-duck years and spent much of his term pushing the Bush agenda, "he never had much chance to develop a distinctive policy identity for the House GOP," Pitney said.
"Gingrich lived for headlines. Hastert was content to let others take the limelight," Pitney said. "Ironically, and sadly, this late-life scandal will probably bring him more attention than anything that he ever did as speaker."
The Associated Press contributed to this report.