Mayor Michael Bloomberg said Monday that the city is "studying our options" after a judge ordered them to release a consultant's review of its 911 system that the mayor has been fighting to keep private.

City lawyers argue that the potentially blistering review is still a draft. They say an order to release it could prevent policymakers from freely expressing their opinions in the future.

"I don't know how any government would be able to function if you had to put out every single paper at the beginning of a study," Bloomberg said.

But Supreme Court Justice Arthur F. Engoron said Monday that his decision stemmed from a belief in open government and transparency.

"The city's not the only interest group here. And the city's not infallible," Engoron said after comparing the city's claim that the report should be private to President Richard Nixon's claims of executive privilege during the Watergate scandal.

Engoron says that the report and all its drafts by the taxpayer funded consultant belong to New York City residents.

Lawyers for the city had argued that the review, commissioned after a massive blizzard in December 2010 that stranded ambulances and backed up the emergency call system, is still in draft form. They claimed that an order to release the documents could have a chilling effect on city employees, who might become reluctant to freely express their opinions.

"If policymakers felt they could not give or receive blunt or candid feedback without it being publicized, the entire public would be at a detriment," said city lawyer Gail Mulligan.

Kate O'Brien Ahlers, a spokeswoman for the city's Law Department, said the city was very disappointed with the ruling and would consider appealing.

Kathleen Horan contributed reporting.