A former Minneapolis landlord dogged for years by accusations of poor housing conditions, fraud and pest infestations was convicted Friday of lying in a court filing aimed at shaking off legal action by upset tenants.

A jury of five women and seven men convicted Stephen Frenz in Hennepin County District Court on one count of felony perjury.

Frenz, 56, of Minneapolis, declined to comment after the verdict was delivered.

Frenz is scheduled to be sentenced on Dec. 20. While the offense carries a possible maximum sentence of five years in prison and/or a fine of $10,000, Hennepin County Attorney Mike Freeman said it's unusual for anyone to serve time for perjury, an offense he could not recall his office ever taking to trial.

Senior Hennepin County Attorney Susan Crumb, who prosecuted the case, said the presumptive sentence for Frenz given his criminal record, which includes traffic offenses, is probation. Crumb said she and her co-counsel, Assistant Hennepin County Attorney Diane Krenz, will consider asking a judge to sentence Frenz to some jail time. She did not specify a possible amount.

"This is one of those cases when we are personally pleased because there are just a lot of people he's injured and harmed, including his own employees … and particularly these tenants," Freeman said. "This [perjury] was blatant."

The issue began in January 2016 when a group of tenants at Frenz's property in the 3000 block of S. 14th Avenue filed a petition for emergency intervention by the court. They said the building wasn't adequately heated and was "infested" with roaches, bedbugs and mice.

Frenz filed a motion asking a housing court referee to dismiss the case and signed a supporting affidavit that included false information, according to evidence presented at trial.

Frenz used the identities of two real people and a third untraceable man to falsely report that three units in the building were occupied, according to evidence. Prosecutors told jurors the ruse was meant to persuade the referee to throw out the case since state law requires a majority of occupied units to approve the petition for it to move forward.

Frenz's attorneys, Robert Sicoli and Paul Engh, vowed to appeal his conviction, alleging missteps by Ramsey County District Judge Robert Awsumb, who presided over the case to prevent a conflict of interest.

"We're disappointed in the verdict, but it's not over yet," Sicoli said. "We believe the judge made significant errors in the jury instructions and other errors during the trial that we intend on appealing."

Sicoli said Awsumb gave jurors incorrect instructions on the elements of perjury, but declined to address specifics. He said Frenz was doing "fine" and declined to comment on Frenz's future.

Frenz managed 1,400 units at one point in his approximately 22-year career as a landlord and property owner. While he was stripped of his rental license in 2017, he still maintains ownership of some buildings, including five apartment complexes in the 3100 block of S. 22nd Avenue that remain in limbo as tenants seek to buy the properties as a cooperative while Frenz moves to evict them.

Chloe Jackson, one of the tenants on S. 22nd Avenue, said the conviction was a victory for Frenz's former tenants.

"Justice is served," she said. "I feel like it's a start, because if he's lied about those buildings, you know he's been lying about all the other buildings."

Prosecutors told jurors that Frenz knew he was under oath because although the 2016 affidavit did not include the word "oath" or warnings of perjury, it included other legal language that indicated an obligation to the truth. They also presented three previous affidavits signed by Frenz that included the phrase "on oath" or "under oath."

Defense attorneys had argued that Frenz's longtime notary had not given him an oath for the 2016 affidavit, so he should be acquitted.

Juror Chad Giefer said jurors struggled with what constituted taking an oath.

"That was the hardest part," Giefer said.

But once jurors agreed that the prosecution was correct, they debated whether Frenz knew he was under oath when he signed the affidavit.

Giefer said the three other affidavits presented by prosecutors convinced them Frenz was guilty. Jurors thought it was suspicious that the phrase "on oath" or "under oath" was omitted from the 2016 document, Giefer added.

"The fact that it was removed was a big thing for us," he said.

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