The man who led the U.S. government's investigation of Michael Vick's dogfighting case said that he's withholding judgment on Vick's rehabilitation.
"Do I think he's changed? I don't know," said retired U.S. Department of Agriculture senior special agent Jim Knorr, speaking to ESPN's "Outside The Lines." "I would hope he has but I don't know. Only one person knows and that's him.
"The only way the public is going to know if he's sincere is to revisit it five to eight years from now, when he's not playing in the NFL and getting endorsements," Knorr said. "Is he still going into the neighborhoods, preaching to the kids?
"If he's sincere or not, it doesn't really matter because what he's doing now, he's doing a positive thing by speaking to kids in the community about his mistakes and telling them not to go there. What he's doing is good for the public."
Knorr talked for the first time since he discussed the case with author Jim Gorant for his book "The Lost Dogs." He said he met Vick "four, five times" during the investigation.
Vick was "always polite and respectful," Knorr said, but added that Vick didn't come clean with authorities about his role in the killing of dogs until after he took a lie-detector test.
Knorr also recalled how one confidential informant he wrote about in his USDA report noted that Vick's adrenaline "would go up, he'd get a high when the group [Vick and his co-defendants, Quanis Phillips and Purnell Peace] were killing [the dogs]."
In 2007, Vick was convicted of a felony related to a dogfighting ring and served 19 months in prison. He has spent the past two seasons with the Philadelphia Eagles, and was named the 2010 NFL Comeback Player of the Year by The Associated Press.
Last week, Dallas mayor pro tem Dwaine Caraway gave the key to the city to Vick, causing an uproar among animal rights activists.
"He had a great year and a great comeback, but there were times where we watched the game, and I know it's bad to say, but there were times where we hope he gets hurt," Buehrle told MLB.com. "Everything you've done to these dogs, something bad needs to happen to these guys."
Knorr said that the public's perception of Vick depends on whether a person owns a dog.
"I think 25 percent of people are for him -- those are the football fans -- 25 percent of people hate him and 50 percent are right in the middle," Knorr said. "A lot of Eagles fans didn't like it when the team first signed him. If he had a horrible season, would Eagles fans still be supporting him?"
Knorr, who owned a dog at the time of the 2007 investigation, said he had to separate his personal and professional lives. He conceded that it wasn't easy when he returned home to see his dog, BJ, after he supervised the digging up of the site where some dogs who didn't perform well had been hanged, then drowned and buried by Vick, Peace and Phillips in the backyard of Vick's house in Surry County, Va.
"I had the scent of the dead dogs on my clothes and when I got home late [the night federal agents first dug up the dead dogs]," Knorr said. "BJ -- who was always sitting by the window waiting for me and would be there to greet me -- went sniffing around and went berserk barking, smelling the death of the dogs on me. I basically went down into the garage and stripped down there, so I could go back in and take a shower and wash the clothes the next day. BJ smelled the death of the dogs on my pants."
Kelly Naqi is a reporter for ESPN's "Outside the Lines."