WASHINGTON (CNN) -- A Halloween party where a Department of Homeland Security worker won praise for a costume of darkened skin and prison garb may stall Senate confirmation of the party's host for a second time.
Julie Myers, head of Immigration and Customs Enforcement, called the man's costume "offensive."
Missouri Democratic Sen. Claire McCaskill said Wednesday that she has placed a temporary "hold" on Julie Myers' nomination for the job of assistant homeland security secretary for immigration and customs enforcement until Myers answers questions about the party, including why photographs of her with the costumed employee were destroyed after questions were raised.
"As the leader of that organization, she should have immediately recognized the problem and asked that person to leave," said McCaskill, who has raised previous concerns about Myers' nomination. "And what really happened was, she judged the costume as one that should get a prize and be recognized and she had her photograph taken with the person in the costume -- and only later came back and apologized and said it was a problem."
President Bush used a 2006 recess appointment to put Myers in office after Senate concerns about her inexperience stalled her confirmation. He nominated her again for the job in January.
Myers, 38, was part of a three-judge panel that originally praised the costume -- which featured dreadlocks, black-and-white prison garb and a skin "bronzer" -- for its originality.
She later apologized for what she said were a few "inappropriate and offensive" costumes after other employees complained. The employee who wore the costume has been placed on paid administrative leave pending an inquiry.
ICE spokeswoman Kelly Nantel told CNN Wednesday the photos were deleted because the costume was offensive and because officials feared the images would end up being used on ICE publications and Web sites.
Nantel said Monday the makeup was meant to make the employee "look African-American." But she said it was not immediately apparent he was wearing the bronzer, and most guests "didn't realize he was wearing makeup at all."
McCaskill called that explanation "kind of silly."
"Are we going to argue about what shade of bronzer was used as makeup?" she asked. "Or are we going to talk about the real problem -- and that is, someone decided to put on dreadlocks and a prison outfit and somebody thought that was an original idea, and the head of the organization embraced it.
"That's the bottom line of what happened," she continued. "And that shows a lack of judgment that should in fact be held against her as she is trying to lead an incredibly large and important organization that deals with all kinds of ethnic backgrounds."
McCaskill said she believed Myers would end up being confirmed. But she said Homeland Security Secretary Michael Chertoff should deliver "some kind of reprimand" over what the senator called Myers' lack of judgment in the matter.
Myers had served in Commerce and Treasury Department posts responsible for overseeing crackdowns on money laundering and worked in the White House personnel office before Bush picked her to lead Immigration and Customs, an agency with a staff of 15,000 and a budget of nearly $5 billion.
Her nomination stalled in the aftermath of Hurricane Katrina, when the Bush administration's floundering response to the storm fueled allegations that it had filled critical jobs with unqualified political supporters. Myers is the niece of retired Gen. Richard Myers, the former chairman of the Joint Chiefs of Staff, and is married to Chertoff's former chief of staff.
The Homeland Security and Governmental Affairs Committee sent her nomination to the Senate floor in September, with its chairman, Sen. Joseph Lieberman, telling Myers she had quelled his earlier worries.
But Hawaii Democrat Daniel Akaka, a senior member of the committee, said Wednesday that the controversy "will place a new consideration on her nomination."
Of several leading Republicans CNN asked about the controversy Wednesday, only one -- Sen. Jon Kyl, of Arizona -- came to her defense.
"In terms of job performance, I don't know of anyone who thinks she hasn't done a credible job," Kyl said.
Sen. Susan Collins, the Homeland Security Committee's top Republican, said Tuesday she wants her staff to question Myers about exactly what happened and what her response was.
"I think the incident certainly indicated a lack of judgment on her part," Collins said. But the Maine senator, who supported Myers' nomination in committee, said she would withhold any final judgment until her aides report back.
A floor vote on the nomination had been expected next week, she said.
The controversy prompted the second round of criticism of Homeland Security staffers from their boss in three weeks. In October, Chertoff blasted Federal Emergency Management Agency staffers for holding a fake news conference on the California wildfires.
Referring to the man who wore the costume, Chertoff Tuesday told reporters "people do dumb things."
"I get very perturbed when there is anything that is done that suggests that with respect to the enforcement of the law, we are anything other than even-handed," said Chertoff. E-mail to a friend
CNN's Jeanne Meserve, Mike M. Ahlers, Jim Spellman and Ted Barrett contributed to this report.