But after studying a system in Illinois that sent some innocent men to death row, Ryan now says he couldn't "throw the switch," even on convicted Oklahoma City bomber Timothy McVeigh.
"A lot has happened to shake my faith in a system I really believed in," Ryan told law students at Loyola University Chicago on Monday. "The more I learn, the more troubled I am."
Since 1977, Illinois has freed 13 men from death row and put another 12 to death. That record prompted Ryan to suspend executions in January 2000 and order a commission to study the issue. He said he will not resume executions until he can be sure that every person on death row is guilty.
He has appointed a commission to study the system.
In the past, the governor has said he backed capital punishment if it were applied fairly and left no room for error. But when a student asked him Monday if he could support a flawless death penalty, he responded: "I don't know."
"I'm still struggling with it," Ryan said.
"I couldn't throw the switch on this guy, McVeigh, and he was a terrible guy," he added. "He thought this thing out and went out and killed a whole bunch of people and said that children were collateral to the event, and it didn't matter. He's shown no remorse. I think there may be cause for the death penalty for a guy like him, but I don't know."
McVeigh is scheduled to die by injection on May 16 for the 1995 bombing of the Oklahoma City federal building, which killed 168 people.
Ryan spokesman Dennis Culloton said the governor has indicated in the past that he thinks McVeigh probably deserves to be executed, but he's glad he's not the one making the decision.
"I think he's just speaking as a human being who has been through the gut-wrenching experience of having to decide whether to execute a man," Culloton said.
Before the moratorium, Ryan decided one death penalty case. In 1999, he turned down the appeal of Andrew Kokoraleis, who was convicted of the abduction, rape and murder of a woman in Elmhurst. Kokoraleis was executed by injection.
The governor said Monday that he agonized over the case and ultimately decided there were no doubts as to Kokoraleis' guilt.
"It was an emotional, exhausting experience that I wouldn't wish on anyone," Ryan said.
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