by Todd Feurer, CBS Chicago web producer

CHICAGO (CBS) — Mayor Lori Lightfoot is defending her decision to fire a longtime City Hall spokesman – although she won’t say exactly why she did it – and is chastising reporters for tweeting what she calls “totally false” reasons for the move, in posts citing unnamed sources.

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Lightfoot said she fired Law Department spokesman Bill McCaffrey over the weekend, due to what she called “serious questions about his professionalism and his judgment.”

“On the basis of what I was briefed on, there was support for the decision to terminate him for cause. So he was terminated for cause,” she said Monday morning at an unrelated event.

The mayor suggested McCaffrey had somehow lied about something, but did not elaborate.

“I think I’ve set a pretty clear standard that in anyone who’s going to work in our administration, they have to do their job at a high degree of competence, they have to be a good colleague, and number three they have to have the highest ethical standards; meaning they can’t lie either through omission or commission. I think I’ve set a very clear standard there,” she said.

McCaffrey had worked at City Hall for 15 years as a spokesman for various agencies, most recently at the Law Department.

Sources told CBS 2’s Brad Edwards that McCaffrey was fired because he raised ethical concerns about the Lightfoot administration, but the mayor vehemently denied that she fired someone for raising ethical questions about her.

“No, definitively not,” she said. “As I said, serious issues regarding professionalism and judgment were raised, and as on the basis of that, there was plenty of information to fire him for cause, which is what happened, period.”

The mayor also admonished reporters for tweets about purported reasons for the firing over the weekend, in which they cited unnamed sources.

“I have to say I’m disappointed that, on the basis of a single source, unnamed, that you all are putting this out,” she said.

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Several reporters tweeted praise for McCaffrey over the weekend after he was fired.

“Obviously Bill McCaffrey was your buddy, but I hope that we are not getting to a new standard in media here in Chicago where we have a bunch of unnamed sources that there’s no other information provided,” Lightfoot said. “They’re just throwing out a bunch of chum on the water, and people are biting at it as if it’s the truth, because the things that have been put out that I’ve seen are demonstrably false, and could easily be proven so with a little bit of diligence, which is what I would assume reporters who are serious about this would do.”

Lightfoot also angrily denied that McCaffrey’s boss, Corporation Counsel Mark Flessner, has a residency problem.

“No, that’s totally false, it’s totally false,” she said.

City employees are required to live within the city limits. The mayor’s office said Flessner moved to Chicago on April 19 and was hired as corporation counsel on May 20.

However, before moving to Chicago, Flessner was claiming a homeowner exemption for both his home in Naperville and a condo he owns in Chicago — an exemption that is only available to homeowners at their primary residence.

DuPage County property tax records show a “residential exemption” for Flessner’s home in Naperville from tax years 2015 through 2018. During the same years, Cook County records show homeowner exemptions at Flessner’s Chicago condo.

Homeowners are required to live on any property where they claim such exemptions in DuPage and Cook counties.

The mayor specifically denied that Flessner has claimed homestead exemptions on his property taxes at two separate homes, but her press secretary, Anel Ruiz, later acknowledged Flessner had “mistakenly” claimed the exemptions on both properties before 2019.

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“Now that this mistake has been brought to his attention, he will be paying back the State the amount he received from the additional exemption, which he estimates to be approximately $2,500. Again, this took place prior to 2019, the year in which Mr. Flessner began his employment with the City of Chicago,” Ruiz stated in an email.