The letter, which was sent to the Minneapolis City Attorney's Office, came a day after a report compiled by an attorney hired by the DFL. That letter indicated Karen Monahan's allegations that Ellison once physically abused her could not be substantiated was made public.

The DFL said Monday they would ask the City of Minneapolis Attorney's Office for review. However, the Minneapolis City Attorney's Office declined to review it due to the fact that Ellison's son, Jeremiah Ellison, is on the city council.

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In a letter to the Minneapolis City Attorney's Office, Backstrom declined to review the investigation completed by attorney Susan Ellingstad, as well as any other private investigator, without an investigation by a law enforcement agency.

"As you know, County or City Attorneys do not generally conduct criminal investigations, but rely on law enforcement agencies to do so," the letter read. "That is the way investigations are conducted which involve this office."

Backstrom went on to say in the letter if a complaint is filed, he would," review the matter on a conflict of interest basis."

Andrew Parker, Monahan's attorney, said Tuesday afternoon that Monahan would welcome and cooperate with, "any fair and impartial investigation."

"This about the healing about the healing of Karen Monahan ... and elevating the public discourse and freeing women's voices, " Parker said. "It's not about throwing Keith Ellison in jail, it never has been."

On Tuesday evening, Ellison's campaign issued a statement from his attorney, Carla Kjellberg.

"County Attorney Backstrom rightly determined that law enforcement has no jurisdiction because Ms. Monahan has never made a police report," Kjellberg said.