CHICAGO (WGN) — In just one day, former Democratic Illinois House Speaker Michael Madigan will report to prison to begin serving a seven-and-a-half-year sentence.

The longtime political figure was convicted in February on 10 of 23 counts in a remarkable corruption trial that lasted four months. The case churned through 60 witnesses and mountains of documents, photographs and taped conversations.

Madigan was sentenced to 90 months in prison, along with a $2.5 million fine, the statutory maximum. He has until 2 p.m. Monday to turn himself in.

University of Illinois Chicago political science professor Dick Simpson, who has studied Chicago politics for decades, testified as an expert witness during the trial.

“The evidence was overwhelming, the jury’s decisions on 10 counts, which he was convicted, was clear. There wasn’t any ambiguity and the judge is simply moving ahead with the process,” Simpson said.

Madigan’s 10 federal convictions centered on two key cases: his effort to get former Chicago Ald. Danny Solis appointed to a state board, and a bribery scheme involving utility giant ComEd.

Earlier this month, a federal appeals court denied Madigan’s request to stay out of prison while his legal team appeals his convictions.

“The judge wants to send a clear signal that corruption is not allowed,” Simpson said. “Jail time is not any fun. It’s very difficult and it’s a severe punishment.”

According to Simpson, about 2,500 Illinois public officials have been convicted in federal court and sent to prison since 1976. He hopes this major case will inspire reform, similar to the response that followed former Gov. Rod Blagojevich’s conviction.

As Madigan spends his final hours of freedom, Simpson believes the 83-year-old’s time behind bars could ultimately be shortened.

“With his age, his health problems, and his wife’s health problems, he may well get out of prison earlier, but he will still have to serve jail time,” Simpson said.