This week, Illinois prosecutors dropped all charges against Jerry Hobbs and released him from prison. Hobbs, 39, has been in prison since 2005 for the rape and murder of his 8-year-old daughter and her 9-year-old friend. Last month, a man was arrested in Virginia whose DNA fit the biological evidence found at the crime scene.

I wrote a short piece for Reason last year about the man who prosecuted Hobbs, Michael Mermel, chief of the criminal division for the Lake County, Illinois, State's Attorney's Office.

Mermel's greatest hit might be the case of Jerry Hobbs, who was accused of killing his 8-year-old daughter and her 9-year-old friend in 2005. When Hobbs' attorneys revealed in court that DNA tests showed the semen found in the mouth, rectum, and vagina of Hobbs' daughter didn't belong to Hobbs,Mermel postulated that the semen must have found its way into the girl's body while she was playing in a patch of woods where teenagers were known to have sex. The girl was found fully clothed.

The only evidence against Hobbs was his confession, which he gave after 16 straight hours of interrogation. (His attorneys say he was also up the entire night before, helping in the search for the girls.) False confessions aren't uncommon, especially when there's pressure on police to solve a high-profile murder.

Assistant State's Attorney Mermel has a history of standing behind his hunches, even when DNA shows the state got the wrong guy. When DNA testing came back showing the semen in the underwear of a 68-year-old woman didn't match Bernie Starks, who was convicted in 1986 for the woman's rape and murder, Mermel dismissed the results because the semen came from the victim's clothing. Had it come from the woman's vagina, Mermel said, "I would be standing over there advocating the side that the defense has in the case."

Three years later, defense attorneys were able to find the rape kit. They then tested semen recovered from the woman's vagina. Again, no match. It probably won't surprise you to learn that Mermel didn't keep his word. This time he argued that the woman must have had sex with someone else just before the rape.

In 2005, when DNA testing on another rape and murder victim didn't match his suspect, Mermel again argued that the victim—this time an 11-year-old—must have been sexually active at around the time she was raped and killed.

Even in releasing Hobbs last week, Lake County State's Attorney Michael Waller told the media he still thinks Hobbs was involved in the murders. But he was graciously dropping the charges against Hobbs because after five years, a negative DNA test, and, finally, a DNA match to another man, he could no longer prove his case beyond a reasonable doubt.

How kind of him.