Instead, three separate, overlapping investigations are underway -- the one in the House, one in the Senate and one by the White House.

They are expected to produce three reports about missteps made by government officials -- and offer three sets of recommendations for fixing what went wrong.

And that, said Richard A. Falkenrath, a senior fellow at the Brookings Institution, a centrist think tank in Washington, is bad news for the nation.

"The thing that we might lose is an opportunity to get on a better trajectory in terms of preparing this country for catastrophic disasters," said Falkenrath, who served in the Bush administration's Homeland Security Department.

Other congressional observers and outside experts caution that none of the findings may be considered definitive, and could be contradictory.

"We felt strongly and still feel strongly that there should be an independent commission to investigate the poor cooperation and response to Katrina," said Susannah Goodman, senior legislative advocate for the watchdog group Common Cause.

"I think the process is very politicized, and that is extremely unfortunate."

Goodman added: "At the end of the day, what everybody wants is a set of recommendations that will fix the problems, that will tell us how we can be better prepared for the next disaster."

House and Senate members have cooperated before in conducting major inquiries, most recently following the Sept. 11, 2001, terrorist attacks.

After public pressure, however, an independent commission also was set up to investigate the attacks.