Just days after Illinois’ senior U.S. senator called on President Bush to shorten former Gov. George Ryan’s prison sentence for corruption, DuPage County’s top prosecutor announced he opposes the move.

In his role as head of the Illinois State’s Attorneys Association, Joseph Birkett sent a letter to the president calling Sen. Dick Durbin’s request “misguided and wrong.”

Ryan was sentenced in 2006 to 6 1/2 years in prison after being convicted on 18 counts of public corruption dating back to his time as secretary of state and stretching through his term as governor.

Durbin announced Monday that he is asking Bush to commute the 74-year-old Ryan’s sentence to time served, citing the former governor’s age and his wife’s frail health.

Birkett said those reasons do not justify an early release from prison.

“While we empathize with Ryan’s family and their plight, I do not believe the hardships they face in his absence are reason enough to free inmate George Ryan,” Birkett said. “All inmates have families, not just those who led privileged lives prior to their incarceration. The suffering faced by former Gov. Ryan’s family is no greater than that experienced by the families of thousands of other inmates across Illinois. 

“That Sen. Durbin would ask for special treatment for a man who for decades enjoyed special treatment at the expense of taxpayers is a slap in the face of justice,” he said.

The issue of clemency for the disgraced former governor has divided Illinois politicians, sometimes blurring party lines.

Birkett, who is weighing a run for governor in 2010, is joined by fellow Republicans such as U.S. Reps. Mark Kirk, 10th District, of Highland Park, and Tim Johnson, 15th District, of Urbana, in opposing clemency.

Durbin and Democratic Gov. Rod Blagojevich — whose own administration has been dogged by corruption investigations — have supported early release for Ryan. Democratic Attorney General Lisa Madigan, also a potential 2010 gubernatorial candidate, is opposed.

President-elect Barack Obama, meanwhile, has declined to enter the fray.

The White House has not indicated whether Ryan’s sentence will be commuted before the end of Bush’s term.

Ryan is currently serving his sentence at a medium-security federal prison in Terre Haute, Ind.