Spencer Platt/Getty Images

A federal judge on Tuesday revoked bail for Bernard B. Kerik, the former New York police commissioner who is facing conspiracy and fraud charges.

Judge Stephen C. Robinson of Federal District Court in White Plains said Mr. Kerik could not be trusted to honor a consent order prohibiting him from revealing confidential information. The judge cited an email that Mr. Kerik sent to the head of his defense fund that apparently included such information.

Mr. Kerik had been allowed to remain free on $500,000 bail, which was secured by his house in New Jersey. The judge turned down a request by Mr. Kerik’s lawyers to keep him from being put behind bars for 48 hours while they prepare an appeal.

Before revoking the bail of Mr. Kerik, Judge Robinson described him as a “toxic combination of self-minded focus and arrogance, and I fear that combination leads him to believe his ends justify his means.”

“He sees the court’s rulings as an inconvenience,” Judge Robinson said, “something to be ignored, and an obstacle to be circumvented.”

After the proceeding, Mr. Kerik loosened his tie and removed papers and a wallet from his pockets. He then carefully took off a chain and medallion and handed it to one of his lawyers. He was led away, not in handcuffs, by court officers.

Jury selection in the trial is to begin Monday. Mr. Kerik was indicted in November 2007 on corruption, conspiracy and tax fraud charges, and he was arraigned on Dec. 29, 2008, on additional charges that he prepared false tax returns. He pleaded not guilty.

Mr. Kerik served as the city’s correction and police commissioners under Mayor Rudolph W. Giuliani, and he gained an international reputation after the Sept. 11 attacks as he was often at Mr. Giuliani’s side.

Two years after he left office, Mr. Kerik was nominated to lead the Department of Homeland Security, in part because of Mr. Giuliani’s recommendation.

Mr. Kerik soon withdrew the nomination, citing his failure to pay taxes on an illegal immigrant whom he had hired as his nanny. News reports soon followed, exploring financial entanglements and ethical problems that led the city to begin an investigation.

During a hearing last month, Judge Robinson criticized Mr. Kerik and his lawyers for what he said were various offenses committed by a lawyer who heads Mr. Kerik’s legal defense fund. The judge said the lawyer, Anthony K. Modafferi, sent e-mail messages to him and to The Washington Times that defamed government prosecutors.

Mr. Modafferi violated a consent order because in some of his e-mail messages, he leaked information that indicated he was privy to sealed court papers, Judge Robinson said at last month’s hearing. The judge then ordered Mr. Kerik to file an affidavit detailing his legal arrangement with Mr. Modafferi, whom the judge said may end up being called to testify in documents or in court.

The judge now believes that Mr. Kerik sent Mr. Modafferi an email containing the information that the lawyer then passed along. It was that email that apparently violated the consent decree, causing Mr. Kerik to be jailed. The specifics details that should not have been released were not revealed on Tuesday.