Dennis Hastert is finally expected to take the walk of shame Tuesday that so many Illinois politicians have walked before and answer to the jaw-dropping allegations federal prosecutors leveled against him late last month.

But the former U.S. House speaker will now do so with help from Thomas C. Green, a high-powered white-collar criminal defense lawyer based in Washington, D.C., whose roster of clients include players in some of the nation’s most notorious scandals — including Watergate, Whitewater and Iran-Contra.

Green filed his formal appearance as lead counsel Monday on the eve of Hastert’s highly anticipated arraignment in the courtroom of U.S. Judge Thomas M. Durkin, a two-time Hastert donor. Green, of Sidley Austin LLP, declined to comment on Hastert’s indictment in an email to the Chicago Sun-Times.

ABC News reported Monday evening that Hastert left his vacation home in Wisconsin early Monday, driving with his wife in a black SUV on the four-hour journey to his home in Plano, Illinois.

The sight of Hastert, once second in line to the presidency, in a courtroom is sure to fill Chicago’s Dirksen Federal Courthouse with hordes of media and curious spectators. And all the while, new attention is being paid to a civil case involving Hastert filed earlier in Chicago.

When Hastert arrives at the courthouse for his 2 p.m. arraignment, he will likely be forced to walk through the front door and make his way through a metal detector like any common defendant. A U.S. Marshals spokeswoman said Monday its policy is to give no preferential treatment.

News cameras would then capture his image as he makes his way past reporters to an elevator and up to Durkin’s stately 14th floor courtroom — where members of the public wishing to attend the hearing may begin lining up at 11:30 a.m.

When the hearing begins, Hastert will be formally notified of the charges against him and asked to enter a plea. The hearing will likely be brief but closely watched given Hastert’s silence since his May 28 indictment. He is charged with lying to the FBI and structuring bank withdrawals as he paid $1.7 million to allegedly conceal sexual misconduct that occurred sometime between 1965 and 1981, according to the grand jury indictment and sources. He had agreed to ultimately pay $3.5 million, the grand jury said.

Even the identity of Hastert’s lawyer remained a secret until Monday, when Green finally emerged as lead counsel in Hastert’s case. Green represented former Assistant Attorney General Robert Mardian during Watergate, several government officials during the Whitewater independent counsel investigations and Ret. Major Gen. Richard V. Secord during the Iran-Contra investigation.

The formal federal prosecutor has practiced law in Washington for more than 40 years, according to his online biography.

John N. Gallo, a partner at Sidley Austin based in Chicago, also filed an appearance Monday as Hastert’s local counsel. Gallo previously represented Wisconsin Gov. Scott Walker in an investigation conducted by the District Attorney in Milwaukee County, according to his biography. And as an assistant U.S. attorney in Chicago, Gallo was the lead prosecutor in the “Operation Silver Shovel” public corruption investigation.

The Hastert case also marks a significant first test for U.S. Attorney Zachary Fardon, who became Chicago’s top federal prosecutor in October 2013. He has assigned Assistant U.S. Attorneys Steven Block and Carrie Hamilton to the case.

While Tuesday’s arraignment will focus exclusively on the criminal charges filed against the Illinois Republican, new scrutiny is being given to a case filed in July 2013 by attorney Michael K. Goldberg on behalf of a former business associate of Hastert’s — J. David John.

John had a falling out with Hastert, and his lawsuit states he discussed allegations with the FBI that Hastert misused government funds.

“My client was surprised by the criminal indictment and has no idea if his communications with the FBI — as set forth in his False Claims Act complaint — led authorities to investigate the criminal allegations against Mr. Hastert,” Goldberg said. “Both matters involve allegations of financial impropriety, but we have no reason at this time to believe that they are related.”

The civil lawsuit claims Hastert violated the False Claims Act by using government money to pay for the office and staff he was allowed to have for five years after he left as speaker. He was supposed to use the office for government business, but it’s alleged he conducted private business there, too.

While the John lawsuit has been dismissed twice, Goldberg has a June 18 court date where he will try to resurrect the case.