Mayor Brandon Johnson on Tuesday declined to veto a $16.6 billion spending plan passed by his rivals on the City Council, allowing it to go into effect without his signature.

"I will not veto the budget approved by the Chicago City Council," Johnson said at City Hall. "I will not add my signature affirming the budget as presented. In this moment, I will not add the risk and speculation of a government shutdown to the profound worries Chicagoans face."

The mayor's decision averts an unprecedented city government shutdown at the end of the year. The city must have a spending plan in place by Dec. 30, or wouldn't be able to pay city workers or contractors in the new year. Essential workers such as police officers and firefighters would have to work without pay.

Johnson had raised objections to a measure in the budget backed by his opponents that allows the city to sell a portion of the debt owed to the city for unpaid fines and fees. The mayor's opponents have estimated that would allow the city to bring in about $90 million in revenue in 2026, but Johnson has called that proposal "immoral."

In a bid to limit the impact of that debt collection on the city's poorest residents, Johnson signed an executive order prohibiting the city from selling individual city-administered medical debt, and establishing rules for selling debt owed to the city.

Johnson said that approximately $800 million in medical debt is owed to the city, and his executive order prevents the city from selling that to debt collectors.

The mayor also signed a second executive order requiring the mayor and City Council to approve any police overtime spending above what has been budgeted for in 2026. The Police Department has regularly spent more than its allotted overtime budget in the past several years.

Under the order regarding police overtime, any overtime requests beyond what is approved in the 2026 budget would have to be reviewed by the Office of Budget and Management at least three months in advance. Requests for additional overtime would have to outline the operations requiring additional overtime; the districts, units, or job titles affected; the funding source to be used to pay for it; and any steps taken to limit excessive overtime and support officer wellness.

The City Council approved a $16.6 billion spending plan opposed by the mayor last week; with a 29-19 vote to approve the tax revenue package to fund it on Friday and a 30-18 vote to approve the rest of the budget on Saturday.

While the spending plan backed by the mayor's rivals passed without a veto-proof majority, members of the opposition bloc behind the budget have expressed confidence that an actual veto would have convinced more alders to join them in overriding Johnson, rather than risk a shutdown.

In lieu of the controversial corporate head tax backed by the mayor, his opponents' budget will rely on an increase in the city's plastic bag tax; overhauling the tax on off-premise liquor sales; legalizing video gambling terminals in Chicago; and opening up new advertising opportunities, such as naming rights for bridge houses along the Chicago River, selling banners on light poles, and placing ads on city vehicles.

It also proposes bringing in nearly $90 million from selling some debt owed to the city for unpaid fines and fees, a proposal the mayor has called "immoral."

Johnson said he could seek changes to the approved budget even after the beginning of the year, though he declined to elaborate.

"We all agree that the budget is a living document, and so there are elements of this budget that we already have flagged that we'll start to go through a process to ensure that the numbers are matching," he said.

The mayor's budget team has argued the alternative budget plan will leave a $163 million shortfall that would have to be filled midyear with spending cuts, layoffs, or new taxes.

Johnson's critics said their budget plan includes $46.6 million in spending cuts and other efficiencies, but the mayor's budget team estimated their proposals would save only $6 million, claiming many of their proposals already were in the mayor's budget plan, or are simply not feasible.

Aldermen also estimated $6.8 million in new revenue in 2026 from legalizing video gambling, but the mayor's budget team claimed that move would result in a loss of $3 million next year, because it would force the city to lose out on $4 million payment from Bally's casino, and only a small fraction of businesses who apply for a video gaming license would actually get approved in 2026.

In proposing to increase the city's plastic bag tax from 10 cents to 15 cents per bag, aldermen estimated $8.7 million in new revenue, while the mayor's budget team claimed that move would generate only $5.2 million, due to a likely drop in shoppers using plastic bags.

The alternative budget estimated $6 million in new revenue from a new 1.5 tax on off-premise liquor sales, replacing the current volume-based tax, with different rates for beer, wine, and spirits. However, the mayor's budget team estimated that move would actually result in a $4.2 million loss for the city.

The biggest sticking point for the mayor's budget team was aldermen's proposal to bring in $89.6 million from selling some debt owed to the city for unpaid fines and fees. Johnson's aides said the plan is simply not feasible and wouldn't generate actual money from the city, claiming there is no realistic way to find investors to buy debt for things like unpaid parking tickets when the city has no authority to seize vehicles or place liens on property for such debt.

The mayor's team also cast doubt on the aldermen's plan to bring in an estimated $6 million by allowing "augmented reality advertising" on city property in games or apps like "Pokemon Go." Johnson's aides said, because no other cities have allowed such advertising, it would require lengthy research for the city to set up a legal framework for such a proposal, making it virtually impossible for the city to make any money from such a venture next year.

The last time a Chicago mayor vetoed a budget approved by the City Council was in 1984, amid the infamous "Council Wars" under Mayor Harold Washington. In that case, the mayor and his opponents — a group of largely White alderpeople led by now-convicted former Alds. Edward Burke (14th) and Ed Vrdolyak (10th) — reached a compromise to pass a budget just hours before the year-end deadline after Washington's rivals couldn't override his veto.