Asked a question about the potential role his work as a McKinsey & Company consultant played in massive layoffs that shook Blue Cross Blue Shield of Michigan in 2007, South Bend, Indiana Mayor Pete Buttigieg deflected Tuesday night by accusing Medicare for All supporters of being the real job-killers—an attack progressives condemned as "incredibly dishonest" and "depraved."

"I don't know what happened in the time after I left, that was in 2007, when they decided to shrink in 2009," Buttigieg, a 2020 Democratic presidential candidate, told MSNBC's Rachel Maddow. "Now, what I do know is there are some voices in the Democratic primary right now who are calling for a policy that would eliminate the job of every single American working at every single insurance company in the country."

While Buttigieg did not attach names to the "voices" or "policy" he referenced, it was immediately clear that his criticism was aimed at fellow 2020 contenders Sens. Bernie Sanders (I-Vt.) and Elizabeth Warren (D-Mass.) over their support for Medicare for All.

Asked by @maddow about a McKinsey client laying off thousands of insurance company workers — and whether Buttigieg’s work played a role — Buttigieg turns it around and warns that Medicare for All advocates would end every insurance worker’s job. pic.twitter.com/hbTGbkcFRR — Dan Diamond (@ddiamond) December 11, 2019

Medicare for All proponents were quick to denounce Buttigieg's attack as highly misleading, noting that Sanders' Medicare for All Act of 2019 includes support for insurance industry workers displaced by the transition to a single-payer system.

"Buttigieg's work for McKinsey almost certainly led to downsizing at Blue Cross, but he's firing back by saying that Medicare for All will destroy all insurance jobs—without mentioning that Bernie's bill contains a provision for compensation and retraining," tweeted Jacobin's Meagan Day, a vocal supporter of Sanders.

"The current system is built to deny people medical care and sock them with huge bills. Pete's healthcare plan protects this system. Now we have a clearer understanding of why."

—Wendell Potter

"To put it another way, Buttigieg helped an insurance giant increase profits at the expense of workers," Day added. "Now he's in trouble for it and he's frantically tossing out insurance industry talking points against Medicare for All."

Ryan Cooper, columnist for The Week, slammed Buttigieg's criticism of Medicare for All as fallacious and said "it would be relatively easy to transition redundant admin[istrative] busywork jobs to actual productive employment."

"It is lunacy to preserve a jalopy healthcare system that is devouring the economy and killing people by the tens of thousands just to preserve a few million pointless jobs," said Cooper. "Even halfway decent labor force management could slot them into new positions over the transition."

Buttigieg's latest volley against Medicare for All came after the mayor, in the face of mounting pressure, finally released the names of the clients he worked for during his tenure as a management consultant at McKinsey.

The list of clients, named in a Medium post published late Tuesday, includes Best Buy, Loblaw's, the U.S. Department of Defense, the Natural Resources Defense Council, and the U.S. Postal Service.

Buttigieg's first project as a McKinsey consultant was with Blue Cross Blue Shield of Michigan, where he said he "was assigned to a team that looked at overhead expenditures such as rent, utilities, and company travel."

In an interview with The Atlantic, Buttigieg said "it's tough for me to say" whether his work influenced Blue Cross Blue Shield's decision in 2009 to freeze pay for non-union workers and lay off 1,000 employees, nearly 10 percent of its workforce. The restructuring recommended by McKinsey at the time also included rate increases.

Wendell Potter, a former insurance executive-turned-whistleblower who predicted earlier this week that Buttigieg's client list would include Blue Cross Blue Shield, said Tuesday that he "can understand why Pete might try to minimize his role now, and make it seem like he was learning how to do spreadsheets."

"The bottom line (that I know too well as a former health insurance exec) is this: The current system is built to deny people medical care and sock them with huge bills," Potter wrote in a series of tweets. "Pete's healthcare plan protects this system. Now we have a clearer understanding of why."