Wisconsin Judgment Day, the Sequel

The ad tells viewers that Butler's focus on "needless technicalities" in the case nearly allowed a murderer to go free. But what the ad calls "a technicality" involves an unsettled area of law tied to a fundamental constitutional right. And it's hard to argue that he "almost jeopardized the prosecution of a murderer" when the court's vote was 6-1, with Butler the only justice dissenting.

On Dec. 3, 1998, 40-year-old Julie Jensen was found dead in her home, poisoned by ethylene glycol (commonly found in antifreeze). Her then-husband, Mark Jensen, was charged with her murder in 2002.

Julie Jensen had told a neighbor and others that she thought her husband was trying to poison her. And she left a sealed letter with the neighbor, asking him to give it to the police if anything happened to her. The handwritten missive, which was delivered as instructed, described her fears about her husband and said that she was not suicidal. She wrote, in part: "I pray I'm wrong + nothing happens ... but I am suspicious of Mark's suspicious behaviors + fear for my early demise. However, I will not leave David + Douglas." (David and Douglas were her sons.)

The fact that the letter was addressed to police made it, in legal terms, "testimonial evidence," or evidence similar to testimony given by a witness in court. And the confrontation clauses of the U.S. and Wisconsin constitutions guarantee the right of an accused to confront the witnesses against him or her. Things get complicated when, as in this case, the witness is unavailable – dead, for example. And not only dead, but possibly dead by the defendant's own hand. In fact, the alleged cause of the unavailability of this witness was the very crime for which Mark Jensen was being tried.

Whether such evidence can be admitted and presented to a jury is not an open-and-shut legal question. The "forfeiture by wrongdoing" doctrine – whereby a defendant is considered to have forfeited his right to confront an unfriendly witness if his own wrongdoing caused the witness to be unable to appear – is by no means settled law. In the Jensen case, the trial judge declared the letter inadmissible on the basis of a 2004 decision by the U.S. Supreme Court.

The prosecutor appealed to the state Supreme Court. And six of the justices ruled his way – but they made clear they were forging a new legal path as they did so: