In an order on Tuesday, Justice Frank Nervo of the New York state court in Manhattan said he will consider whether to issue a temporary restraining order (TRO) at the Dec. 14 hearing.
Nervo has not ruled on the mandate's merits. He issued an order on Wednesday clarifying that he had not "issued a stay," following incorrect media reports that he had issued a TRO. The city says the mandate remains in force.
Mayor Bill de Blasio had on Oct. 20 announced the vaccine mandate for New York City's approximately 160,000 public-sector employees, a group that includes police, firefighters and sanitation workers.
Vaccinations had been mandated in September for city teachers and healthcare workers, and most have been vaccinated.
About 94% of the city's 378,000 employees are vaccinated, up from 86% in late October, de Blasio's office said on Monday.
The mayor on Monday said New York City would also require private-sector workers to be vaccinated by Dec. 27, a first-in-the-nation mandate affecting about 184,000 businesses.
"Vaccination is the way out of this pandemic," de Blasio said.
His successor, Eric Adams, takes office in January.
Most courts have rejected legal challenges to various vaccine mandates imposed in New York City and state.
A federal appeals court in New Orleans last month put on hold President Joe Biden's nationwide vaccine mandate for companies with at least 100 workers.
Biden, de Blasio and Adams are Democrats.
The lead plaintiff in the public-sector mandate case is Anthony Marciano, a police detective on the force for 10 years.
He said he has natural immunity after recovering from COVID-19 and that requiring him to get vaccinated violated his constitutional and civil rights.
(Reporting by Jonathan Stempel in New York; Editing by Lisa Shumaker)
By Jonathan Stempel