Bush, White House Chief of Staff Andrew H. Card Jr., senior adviser Karl Rove and Dina Powell, head of presidential personnel, are usually the only ones outside the counsel's office aware of the selections. Once the pick is made, the counsel's office vets the candidate, asking scores of questions about personal relationships and finances, professional dealings, and criminal or improper behavior.
Records are reviewed and potential problems investigated. If nothing problematic arises, Bush makes the announcement -- often before the FBI has conducted a background check. The FBI check is completed before the Senate confirms each pick.
The efficacy of Bush's process is in the results, officials said: Kerik is the second nominee in two terms to be withdrawn. Bill Clinton, by comparison, had two attorney-general nominees forced out and six total in two terms.
Current officials dismiss criticism, saying it is virtually impossible to stop candidates from withholding information or lying to White House investigators. White House press secretary Scott McClellan said Bush remains confident about the screening process.
"The vetting process is a thorough and extensive one," McClellan said. "It's a process that looks at all the issues related to the nominee's financial, professional and personal background. It was Commissioner Kerik himself who said this was a matter he should have brought to our attention sooner."
The White House officials quoted anonymously in this story are in a position to know details of the controversy, and refused to speak on the record because they are not authorized to discuss the secretive selection and vetting process. Kerik's version of events, which did not differ from the White House's, was provided by his lawyer; Rudolph W. Giuliani, the former New York mayor and business partner of Kerik's; and Kerik himself.
Giuliani, who recommended Kerik for the post, also called the White House yesterday and apologized.
The Homeland Security Department has sparked controversy for Bush since its inception. He initially opposed the department but succumbed to pressure from Democrats and Republicans in Congress to create it. Then Bush was criticized when some GOP allies questioned the patriotism of Democrats such as Sen. Max Cleland (Ga.) for refusing to embrace the president's version of the department.
Once it was up and running, the department served up two of the most ridiculed White House decisions of the first term: alerting the public to buy duct tape and plastic sheeting in case of a terrorist attack, and implementing a confusing color-coded terrorism alert system.
More than two years after its creation, the department is viewed by many Democrats and Republicans as too bureaucratic and in dire need of a shake-up and strong leadership. Kerik, a tough-talking former street cop, was viewed by Bush as the perfect panacea. Bush hailed the former police commissioner as tough enough to guard the nation from future attacks.
The two shared an emotional bond over the Sept. 11, 2001, terrorist attacks, which forced the two men to help comfort the nation, rebuild a city and launch a worldwide hunt for the perpetrators.
White House officials said senators, including several Democrats, confirmed that the nomination was on track, despite a host of questions about Kerik's quick riches after leaving public office and his responsibility for training the Iraqi police force on a mission for the administration.
The nanny problem put a quick end to the nomination, just as it did for Linda Chavez as Bush's first nominee for labor secretary, and three high-profile nominees for Clinton: Zoe Baird, his first choice as attorney general; Lani Guinier, who had been chosen to head the Justice Department's civil rights division; and Kimba M. Wood, a federal judge whose nomination as attorney general did not go forward.
Kerik told reporters yesterday that he discovered on Wednesday he had not paid taxes on a Mexican-born nanny and housekeeper who was probably working illegally in the country. Tacopina, his lawyer, said she worked for Kerik for about 18 months and had returned to Mexico six weeks ago, in keeping with a plan she had for several months. Tacopina called the nanny question "the sole reason he withdrew."
Kerik insisted he was unaware of the problem until last week; White House officials privately said he was lying or showed terrible judgment.
Kerik told the reporters on his lawn that over the previous two days or so, he "came to realize that in addition to some of the tax issues that I thought I may have, there may have been a question with regard to her legal status in this country."
Staff writer John Mintz and researcher Karl Evanzz contributed to this report.