Members slammed Mayor Mamdani and his administration for skipping the meeting.
Critics have questioned how the tax is being implemented and why some homeowners were mistakenly put on the list.
"We're asking basic questions about how a major tax was administered," Frank Morano of the NYC Council said.
Members of the New York City Council took out their frustrations on empty chairs on Tuesday.
"My residents in my district shouldn't have to hire lawyers to prove they live in their own home," Councilmember Phil Wong said.
The council's oversight hearing was intended to get answers about Mayor Mamdani's controversial new tax on luxury second homes. But the administration declined to testify because of a pending lawsuit against the tax.
Instead, the council heard from critics who warned of unintended consequences.
"It's not only billionaires. It's hardworking New Yorkers who dedicate themselves to making this city work that are very concerned about what impact it might have," one witness said.
Earlier this year, the mayor insisted the goal was simple.
"This pied-à-terre tax is specifically designed for the richest of the rich," Mamdani said in a video.
But the city put thousands of homeowners on notice that they could be subject to the tax and gave them a deadline to prove they're not.
"A hit list of the haves and the have-nots, a 'scarlet letter,' letting everyone know that we know who you are and we see you," councilmember Kamillah Hanks said.
The Finance Commissioner provided written testimony, saying the department "is committed to ensuring that this surcharge is only applied to those properties that are subject to the surcharge under the law. Government should communicate clearly and effectively about new policies, and finance is committed to doing that."
Council members insisted that's not good enough.
"I think New Yorkers are entitled to ask a very simple question: What are they hiding?" Morano said.
The Finance Commissioner insists they are hiding nothing and has offered to testify at a future date.
Critics in both parties say people are being presumed guilty unless and until they are 'proven resident.'
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