NEW YORK CITY — The head of a major NYPD union has urged his members to essentially disobey a new department edict about searching someone's home or car without written permission, DNAinfo New York has learned.

That's because the Civilian Complaint Review Board has not yet weighed in on the new rule for when police don't have a search warrant and the union is worried its members will be second-guessed by that group, which investigates police abuse allegations, or even face charges if they comply.

The warning from Louis Turco, president of the Lieutenant's Benevolent Association, was sent in a letter on Monday to 1,720 members just two days after the NYPD’s new “Consent to Search Guidelines” procedures, called Operations Order 50, went into effect.

The rules require officers in detective and investigative commands to first seek permission from someone to search their home, car or property — even when they think a wanted criminal is hiding out — and to try to get that person to sign a consent form.

They must also give out “Contact Cards” with an officer's name, rank and shield number on it, along with a copy of the signed “Consent to Search” form.

“As restrictive and impractical as the procedures are to employ, and even if all the steps are complied with, the circumstances leading up to a person agreeing to sign a Consent to Search form will be subjectively scrutinized by the Civilian Complaint Review Board,” he wrote in his missive.

His union believes that without knowing the board's take on the new rule, his members will be vulnerable to people alleging they were coerced or forced to sign the forms — and the board taking their side.

"I cannot allow my members to be thrown under the bus,” Turco told DNAinfo.

In his mailing, Turco warned his lieutenants to avoid "routinely, proactively and knowingly putting themselves into a situation where a Consent to Search form must be utilized."

A CCRB spokesman, however, insisted it "always" evaluates cases "in a fair and objective manner after evaluating all available evidence."

"This objectivity extends to consent searches under the NYPD’s newly instituted Operation Order 50, and our investigations will continue to be conducted in a neutral and impartial manner," the spokesman added.

But Turco wrote that his members should exercise caution “until the Civilian Complaint Review Board can articulate how (our members) can safely implement the requirements outlined in the Operations Order, and reassure our members that the integrity of their actions will not be routinely questioned and denigrated by baseless allegations."

The NYPD did not immediately comment.