State Rep. John Lesch is not protected by "legislative immunity" in a defamation case brought against him by St. Paul city attorney Lyndsey Olson, the Minnesota Court of Appeals ruled Monday.

The decision allows Olson's case to proceed.

Olson sued Lesch last year after he sent a letter to incoming St. Paul Mayor Melvin Carter criticizing her work history and judgment, saying she has a "track record of integrity questions and management problems."

Lesch, a Democrat who represents part of St. Paul, has sought to dismiss the suit, arguing in part that he has legislative immunity. He will file a petition in the next month with the Minnesota Supreme Court, his attorney Marshall Tanick said.

"The Appellate Court construed the legislative immunity of legislators extremely narrowly, and we think that it's more proper to take a broader view of what legislators do," Tanick said.

He said he hopes the Supreme Court decides to take up the case to provide "clarification and guidance" on legislative immunity.

The Court of Appeals opinion focused on whether Lesch's letter constitutes legitimate legislative activity that should warrant immunity. They affirmed a Hennepin County District Judge's ruling that it was not.

Lesch had argued the letter was intended to get information that would help him work with the city.

He wrote to Carter on Minnesota House of Representatives letterhead under the bold words "PERSONAL AND CONFIDENTIAL."

In the message, he complimented the mayor's inaugural ceremony and offered to counsel him on local government-related data practices issues before the Legislature.

But most of his letter focused on the attorney's office and the decision to hire Olson. Lesch worked in the St. Paul City Attorney's Office for about 15 years. He is a National Guard member, and he requested documents related to Olson's hiring process and past work as general counsel for the Minnesota National Guard.

The appellate judges found the letter was not about any particular business before the Legislature and was a "personal or political" act rather than a legislative one.

The opinion, authored by Judge Lucinda Jesson, stated that if he had read the letter aloud on the House floor, that would have been a different matter.

Olson had requested the courts find Lesch liable for defamation and require he pay her more than $50,000 in damages, as well as attorney fees and other costs.