The hush-money scandal involving former U.S. House Speaker Dennis Hastert will add another name to the list of Illinois politicians convicted of a crime.

Hastert plans to plead guilty to charges of lying to the FBI about his bank withdrawals, which were supposedly structured to mask payments to cover up decades-old sexual misconduct allegations.

U.S. Sen. Dick Durbin (D-Ill.) was Hastert’s colleague in the House for a decade, and says Capitol Hill remains shocked by the story.

“No one saw this coming. Nobody,” Durbin said. “I’ve thought about it long and hard and there was never a clue that he had these problems in his own, personal life.”

Hastert will be the fourth member of Congress from Illinois to be convicted of a federal crime in the past 20 years, a list which included former U.S. Reps. Dan Rostenkowski, Mel Reynolds, and Jesse Jackson Jr. Another ex-congressman, Aaron Schock, is currently under investigation over inconsistencies in his mileage reimbursements.

“It is a sad situation, and we’ve had too many of them in our state when the leaders in both political parties are held accountable, as they should be, for criminal conduct,” Durbin said.

Hastert is due to appear in federal court in Chicago to enter his plea on October 28.