A Senate inquiry into the government's slow response to Hurricane Katrina is being crippled by White House stonewalling, according to senators leading the investigation. The Associated Press reported Tuesday that the Bush administration is blocking officials from answering even routine questions about the times and dates of meetings and phone calls with the White House during the crisis.

According to the report, White House staffers and other federal agency employees have refused to be interviewed by congressional investigators in some cases. "No one believes that the government responded adequately," said Democratic Senator Joe Lieberman. "And we can't put that story together if people feel they're under a gag order from the White House."

A White House spokesperson told the AP that the administration is committed to working with separate Senate and House investigations of the Katrina response (see "Federal Agency Delayed Katrina Response, According To Internal Memo"), but wants to protect the confidentiality of presidential advisers. That answer was good enough for Senator Susan Collins, the Republican chair of the Senate Homeland Security and Governmental Affairs Committee investigating the response. Collins said she respects the White House's reluctance to reveal advice to President Bush from his top aides, which is generally covered by executive privilege.

She did, however, criticize the trickle of information from agency officials about their contacts with the White House. "We are entitled to know if someone from the Department of Homeland Security calls someone at the White House during this whole crisis period," Collins said. "So I think the White House has gone too far in restricting basic information about who called whom on what day." Collins added that it was "completely inappropriate" for the White House to block agency officials from talking to the Senate committee.

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White House spokesperson Trent Duffy said the administration's deputy homeland security adviser, Ken Rapuano, has briefed House and Senate lawmakers on the federal response. He also said a "lessons learned" report from Homeland Security Adviser Frances Fragos Townsend is expected soon (see "Bush Takes Blame For Slow Katrina Response"). Duffy defended the decision to prohibit White House staffers and other presidential advisers from testifying before Congress.

"There is a deliberate process, and the White House has always said it wants to cooperate with the committee but preserve any president's ability to get advice from advisers on a confidential basis," Duffy said, according to the AP. "And that's a critical need for any U.S. president and that is continuing to influence how we cooperate with the committees."

The Senate inquiry is scheduled to conclude in March with a report detailing steps the federal government took — and failed to take — in preparation for the August 29 storm. While investigators have interviewed more than 250 witnesses from federal, state and local governments and the private sector and received an estimated 500,000 documents — including e-mails, memos, supply orders and emergency operation plans — outlining Katrina-related communications among all levels of government, Lieberman said the Justice and Health and Human Services departments have essentially ignored months of requests for documents.

On Tuesday, The New York Times reported that despite public statements in the days following Katrina's landfall, the White House was told in the hours before the storm hit that New Orleans would probably be inundated by floodwater, forcing the evacuation of hundreds of thousands of people (see "White House Was Warned About Hurricane Katrina Flooding"). The Times also reported that the Homeland Security Department warned on August 27 that Katrina could reach or exceed the dire models predicted in a simulated hurricane drill in 2004.

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