Kathryn Schulz’s Being Wrong: Adventures in the Margin of Error, which I’ll probably praise to the skies once I’m through with it, pointed me to a particularly extreme case of post-hoc rationalization in action. It comes from Billings, Montana, where Jim Bromgard was convicted of the rape and attempted murder of an 8 year-old girl back in 1987. Nearly two decades later, DNA evidence collected from the victim’s underwear definitively exonerated Bromgard, who was subsequently released. Bromgard sued the state of Montana for his wrongful imprisonment. In his deposition, then-prosecutor and current Chief Justice of the Montana Supreme Court Mike McGrath spun a series of incredible tales to avoid having to admit he’d gotten the case wrong:

Nearly five years later, Montana Atty. Gen. Mike McGrath — a recently announced candidate for chief justice of the state’s Supreme Court — has stated under oath that he still believes Bromgard is guilty.

In most of the cases where prosecutors have refused to believe in an exoneration, they have cited evidence that more than one person was involved in the crime to argue that the DNA was left by a second, unidentified offender. It is rare for a prosecutor to dispute a DNA exoneration when there is no evidence — as in Bromgard’s case — that more than one person committed the crime.

McGrath, testifying in a deposition taken in a lawsuit brought by Bromgard, cited several possibilities, including that the victim was sexually active with someone else or that her 11-year-old sister was sexually active while wearing her younger sister’s underwear.

The veteran prosecutor also suggested that the DNA could have been from the child’s father and that the girl’s parents had sex on their daughter’s bed and left DNA, or that the father assaulted the girl.

…

“In my experience as a prosecutor, none of those theories is far-fetched,” said McGrath, who has spent 25 years in the criminal justice system in Montana. “All of those are possible.”

Paxinos, informed of McGrath’s views, said, “I had [Bromgard] cut loose because his DNA did not match the DNA in the case. He could not be the perpetrator unless you believed the 8-year-old was having sex with multiple men. That would be far-fetched.”

Montana, your Chief Justice of the Supreme Court.