Bloodlines

After dermatologist David Cornbleet was murdered in his Michigan Avenue office, his son, Jonathan, devoted himself to finding the killer. Now a shy and troubled young man—a former patient of Dr. Cornbleet's—has confessed. But that man's anguished father is arguing that a drug prescribed by the slain doctor may have contributed to the killing.

(page 8 of 10)

Gathering together a few days after the funeral, the Cornbleet family formulated a strategy. The son would handle the media—the more publicity, the better the chance that someone would step forward. Next, the Cornbleets decided on the best way to reach people who might know the killer, a young man. "We [felt that we] needed to come up with a way to attract someone who's in their 20s or 30s," says Jocelyn. "So we asked ourselves, 'How do they communicate? How do they actually talk to one another?'"

Recalling that another family had used YouTube to solicit tips after an accident, Jocelyn suggested putting the surveillance tape on the video-sharing site. Meanwhile, the daughter's fiancé, Dan Drucker, turned to MySpace. "He said, 'We gotta hit the Internet, because the guy's young; his friends are going to be young.'"

Over the next several months, Jon devoted his life to the case. He spent hours in his home office soliciting MySpace "friends." He updated the Web site Drucker had created with any new development. Trudging downtown in the winter cold, he papered the Loop with fliers.

The plan worked. The Web site attracted thousands of hits. Tips poured in. The case landed on numerous TV programs, everything from The Today Show to Inside Edition. Geraldo Rivera devoted a segment to the investigation. The family passed its information to detectives. Jon offered a $25,000 reward.

After an initial flurry, however, the case seemed to stall. Then, last February, a video surfaced. A young man shopping at the Home Depot on North Halsted Street was captured buying an unusual item that had been found at the murder scene. The object, which detectives have not revealed, had been bought on September 30, 2006, more than three weeks before the murder.

At the family's expense and with the blessing of police, Jon turned to a Virginia research firm used by the FBI to enhance the surveillance tapes from Home Depot and 30 North Michigan. The family's hopes soared. Then police gave them the bad news. The young man in the Home Depot video was not the killer. His alibi was airtight.

"We were extremely disappointed," says Jocelyn. "At first, you get a whole lot of hits, a lot of people who view the Web site and give you information. Then all of a sudden it stops. You find DNA at the scene and look through the database and it doesn't match. You have all these leads that didn't go anywhere."

Winter became spring. No new leads, no promising developments.

* * *

Then, one night, 24 weeks after his father's murder, Jon Cornbleet received a message on MySpace from the marine friend of Hans's former roommate. In it, the 25-year-old marine passed along the concerns expressed to him by the roommate and the name of the person the marine believed had killed David Cornbleet: "Hans Rudolph Peterson." Jon called police and then his sister. "This is the one," he told her. "This is the person. It checks out."

Police began to match evidence from the scene to Hans Peterson. "My dad had a card for [him], one of his patient cards, including the date he came in and the prescription my father wrote," the daughter says. While the family waited, fearful that the suspect would somehow elude arrest, detectives assembled the case. They secured a warrant to search Peterson's former New York apartment. They matched DNA found on a cigarette butt to the DNA found at the murder scene.

Jon Cornbleet returned to his father's burial site on June 17th—Father's Day. The weather was warm and humid. Yes, he now knew who the killer was, but the suspect still walked a free man. Jon wept as he once again addressed his father. "I stared at his grave with disgust for myself," he says. "I had promised him the last time that if he gave me the strength that I would bring him justice. . . . I had to tell him, 'I'm doing everything I can, but it's not enough. I'm not getting the job done.' It was horrible."

Eventually investigators located Peterson through a forwarding address provided to them by the marine. On St. Martin, in early July, Hans learned authorities were closing in. He called his mother, Tom Peterson says. "He said, 'Mom, I need you to come down here.'" Then Hans turned himself in. Jackie Peterson, in turn, called her ex-husband. "Hans is in a French prison," she said, "and he confessed to murdering the dermatologist who gave him the Accutane."

Tom Peterson says he didn't believe it. "I thought, Maybe he imagined he murdered the doctor. Then I did a Google search: Chicago, murder, dermatologist. And I watched the videotape of the guy walking into the building. And I thought, 'That's his walk.'"

* * *

This article appears in the December 2007 issue of Chicago Magazine.

Did you like what you read here? Subscribe to Chicago Magazine »