A dispute over the proposed release of a violent serial rapist has erupted into a rare and incendiary feud between two public prosecutors at the heart of the case.

In an unlikely drama playing out in federal court, Hennepin County assistant attorney George Widseth has lashed out at Minnesota Attorney General Lori Swanson over her opposition to the release of Thomas Duvall, 58, from the Minnesota Sex Offender Program (MSOP). Widseth, whose office supported the proposed discharge, wrote a highly personal e-mail to Solicitor General Alan Gilbert, who is representing Swanson's office in the case.

"Are you REALLY the best lawyer that Lori [Swanson] has? Seriously? I cannot wait to spend time in court with you," the e-mail said.

Widseth then wrote that he was sending Gilbert an "article on 'low T' — it might help," apparently a reference to a medical condition known as "low testosterone." Widseth ended the e-mail with, "Yours in Christ," according to documents filed Thursday in federal court.

Swanson fired back with a letter to the federal judge who is presiding over the case, in which she said Widseth's reference to Christ was "curious" given that Gilbert is Jewish. "No other communication by Mr. Widseth to the Court … or other lawyers in the Duvall case contain such a closing," Swanson wrote. A spokesman for the attorney general's office called Widseth's language "troubling."

Widseth did not return calls Thursday. A spokesman for the Hennepin County attorney's office said the matter is under investigation and declined to comment further.

The war of words reflects the heightened public unease as Minnesota struggles to overhaul its treatment system for violent rapists, pedophiles and other offenders.

In less than a week, U.S. District Judge Donovan Frank will rule on the constitutionality of the sex offender program, which currently confines about 700 sex offenders in high-security treatment centers in St. Peter and Moose Lake for indefinite terms. If Frank finds the program unconstitutional, state legislators could be forced to scramble to find less-restrictive treatment options for hundreds of highly stigmatized sex offenders — a challenge that already has produced highly acrimonious debate.

"This is a pretty monumental issue," said Ken Jorgensen, a partner at the Minneapolis law firm Dorsey & Whitney. "It's an emotionally charged issue, and it doesn't surprise me that there are people who feel passionately about it on both sides."

Lawyers said the ad hominem attacks are unlikely to influence the larger outcome of the case, and it remains unclear whether the unusual behavior violates lawyers' professional standards. According to state rules, it is professional misconduct for a lawyer to harass a person on the basis of religion. The Office of Lawyers Professional Responsibility declined to comment Thursday on whether any misconduct occurred.

'Disregarded'

The friction between Widseth and Swanson dates back to at least last October, when Widseth challenged the attorney general's efforts to intervene in the release of Duvall, a serial rapist with a violent past. In a letter to a state Supreme Court appeals panel, Widseth tried to block Swanson's efforts to obtain Duvall's medical records and argued that she was not a party in the case.

A month later, Widseth attacked Swanson's involvement again following a hearing before the Supreme Court appeals panel. Widseth's comments were unusually personal, as he suggested that Swanson was exploiting the Duvall case for political gain. "I was putting away bad guys when Lori Swanson was still in law school," Widseth told a crowd of reporters gathered outside a Dakota County courtroom on Nov. 9th. Widseth then said of Swanson, "She's been more of a politician than an in-the-room attorney."

Widseth renewed his critique in a Feb. 4 letter to Judge Frank, writing, "To me, the Attorney General's efforts in the Duvall case do not suggest merely requesting a thorough review before his release, but instead smacks of a full-scale attack to prevent the release of Duvall who has the full support of his treatment team" at MSOP.

In response, the attorney general's office has argued that Widseth has been insensitive to the concerns of Duvall's victims. In an affidavit filed with the court, one of Duvall's victims describes how, in 1987, Duvall bound her with an electrical cord and repeatedly raped her over a two- to three-hour period, while hitting her with the handle of a hammer. The victim, described as "Jane Doe" in the affidavit, said she "felt disregarded and shut down " during a meeting with Widseth last August.

A spokesman for Swanson's office said Widseth has repeatedly sided against Duvall's victims. "Mr. Widseth's salary is paid for by the taxpayers, but he's acting much more like he's Mr. Duvall's attorney," said Ben Wogsland.

Eric Janus, dean of the William Mitchell College of Law and author of a book on sexual violence policy, said the spat is a preview of the heated political debate that will ensue this spring if state lawmakers are forced to scramble to implement a federally imposed ruling.

"Emotions can get pretty raw on this issue," Janus said. "Lawyers ought to try to avoid that and ought to try to keep it professional."

Staff writer Paul McEnroe contributed to this article. Chris Serres • 612-673-4308 Twitter: @chrisserres