Myers, 36, took the reins of the U.S. Immigration and Customs Enforcement bureau after her June nomination by the White House stalled on Capitol Hill. That prompted President Bush last week to make her a "recess appointment," which does not require Senate confirmation.

The administration hailed her "extensive law-enforcement experience" and Michael Chertoff, chief of the Department of Homeland Security, praised her "judgment and determination" as qualifying her to head the nation's second-largest law-enforcement agency.

That is not the assessment of Myers made by a Border Patrol union leader, Senate Democrats and several immigration think tanks in Washington.

They say someone with a more proven track record is crucial for the bureau, which has a $4 billion budget and more than 15,000 personnel. Among its duties are tracking down and expelling illegal aliens, busting firms that hire employees without "green cards," chasing foreign students and tourists who overstay their visas, and combating child pornography, money laundering, and weapons and drug trafficking.

On Monday, Border Patrol union leader T.J. Bonner criticized Myers' lack of immigration expertise, limited management background and "cozy ties" with Chertoff, for whom Myers served as chief of staff when Chertoff headed the Justice Department's criminal division. Last summer, Myers married Chertoff's current chief of staff at Homeland Security.

"This is not going to help," said Bonner, who is president of the 10,000-member National Border Patrol Council union.

Mark Krikorian, executive director of the Center for Immigration Studies, agreed. He said her lack of experience in the complex area of immigration law will hurt the battle against what he and others call a flood of people crossing U.S. borders illegally and an agency beset by mismanagement and internal turmoil.

"Would you put someone with no experience in tax law in charge of the IRS?" Krikorian said.

The White House has insisted that Myers is well-suited and prepared for the job. Aside from her time with Chertoff at the Justice Department, she also served a stint as a federal prosecutor and as an associate counsel on Clinton-era independent counsel Kenneth Starr's team.

At the Treasury and Commerce departments, Myers oversaw efforts to combat money laundering, financial crimes and export-control law violations. Her biggest supervisory responsibility came at Commerce, where she ran a staff of about 200 and a budget of $25 million. Most recently, she worked in the White House personnel office.

Jim Pasco, executive director of the 321,000-member Fraternal Order of Police, said he was impressed with Myers' abilities when he and his organization worked with her on issues when she was at the Justice department and in the White House.

"Her managerial insight is really striking. She's a natural," Pasco said Monday. "We have always found her to be thoughtful, candid and a person of action."

After she was nominated, Myers was met with skepticism by both Democratic and GOP senators, who said she barely met the legal requirement for five years of management experience.

"The head of ICE should be an individual who has demonstrated extensive executive-level leadership and the ability to manage a budget through reorganizations and budget cycles," said Sen. Daniel Akaka, D-Hawaii, adding that Myers "has not demonstrated this ability."

After meetings with senators to assuage their doubts, Myers was endorsed by the Senate Homeland Security and Governmental Affairs Committee in October on a party-line vote, with nine Republicans backing her and six Democrats voting no.

Ever since, her nomination had stalled, going nowhere until Bush made an end-run around the Senate last Wednesday and placed her in the job.

(Contact Lisa Hoffman at HoffmanL(at)shns.com)