The insurance industry reacted immediately, and with some degree of alarm.

Ernst Csiszar, president of the Property Casualty Insurers Association of America, based in Des Plaines, N.Y., said the lawsuit was about politics. "It threatens the validity of any contract now in effect," he said.

Robert Hartwig, chief economist for the New York-based Insurance Information Institute, said it was noteworthy that not one insurance regulator supported Mr. Hood's lawsuit, including his home state commissioner, George Dale.

Mr. Dale told National Underwriter yesterday that he would obey whatever courts said, but did note that the potential ramifications of the suit could be troubling.

Mr. Hartwig said the wind versus flood issue rarely came up after big hurricanes. "In fact, these claims usually run pretty smoothly. Whether it is flood or just flood and wind, adjusters are very experienced at it," he said.

The problem with Katrina is that many of the affected residents did not buy flood insurance, he added.

Mr. Hood is not arguing that the flood exclusion is invalid, but has questioned its interpretation.

"The provisions at issue attempt to exclude from coverage loss or damage caused directly or indirectly by water, whether or not driven by wind," Mr. Hood said in a press release.

In such disputes, the call should always be in favor of the policyholder, he said.

In a similar vein, Ken Suggs, president of the American Trial Lawyers Association, painted the insurance industry as heartless bureaucrats who even before the storm subsided were a disowning liability.

"The description by some in the industry of the damage from the storm surge as "The Great New Orleans Flood" is ridiculous," he said. "It contradicts the scientific assessment of the National Climatic Data Center, and appears to be the first part of a 'spin' campaign designed to provide cover for denying claims from victims."

Mr. Hood's the lawsuit, which has not been joined by other states, is a legal attack on an industry that follows in the footsteps of his predecessor, Mike Moore, who gained a national reputation suing the tobacco business.

In Alabama, according to a Reuters report, Attorney General Troy King said it would be premature to initiate such a suit. In Louisiana the Attorney General's Office referred questions about possible legal action to the Department of Insurance. A spokesman said there are no plans for a suit and it is not the task of that agency to file legal actions.