Critics who argued that the D.C. City Council's vote to repeal the city's mandatory no-fault car insurance requirement was based on flimsy evidence probably will take little comfort in knowing that the council action will not interfere with the continued search for facts.

Council members Nadine P. Winter (D-Ward 6) and John Ray (D-At Large), who backed the amendments Nov. 19 that made no-fault coverage optional, say they hope to uncover important information about the cost of insurance rates and the behavior of the auto insurance industry during separate forums. Winter will hold an auto insurance debate at a high school in her ward Dec. 14 and Ray plans to conduct hearings "to determine the extent of consumer abuse by the auto insurance industry."

Winter intends to give Government Employee Insurance Co. (Geico) representatives, who opposed the insurance amendments, and area trial lawyers, who lobbied in favor of the amendments, equal time during her forum, which Winter has labeled "Geico vs. trial lawyers" and "the debate of the year."

Winter accused Geico of misleading her constituents through mass mailings that warned policy holders that insurance premiums would increase from 11 to 60 percent without a mandatory no-fault system.

Winter, who argues that some insurance premiums will decrease under the new system, views the debate as a chance for Geico to "face the people" and explain why rates would have to be increased when Geico has excess profits in the millions of dollars.

But the debate, which Winter first announced during a council meeting, may hit a snag.

"We do not plan to participate," said Donn Knight, regional vice president for Geico. "The council has acted, at least for the moment. We don't see how it could be a constructive or useful forum."

On the other side, Lee Norwind, the chief lobbyist for the trial lawyers, said his group had not been notified of the debate. "If we are invited, we will attend," he said.

If the prospects for a debate seem a little shaky at this point, Winter appears to be having better luck with her push for action on a bill that would require insurance companies to return excess profits to consumers.

Ray, who is chairman of the council's Consumer and Regulatory Affairs Committee, says he has been persuaded to take a look at insurance company revenues and operating practices and intends to seek committee action on Winter's bill next month.

"By taking more money from the policy holder, in the form of higher premiums, and by delaying and reducing claims payments to policy holders," Ray said, "the industry has diverted vast sums into very profitable investments, an approach which benefits the industry to the detriment of consumers."

Geico Corp., whose principal subsidiary is the insurance company, reported a net income of $108.7 million for the first nine months of this year.

Winter's bill defines excess profits based on a formula involving earned premiums, actual and anticipated underwriting gains and investment income.

Auto insurers would be required to refund excess profits to consumers in cash or credits on their premiums.

In addition to considering Winter's bill, Ray plans to hold hearings on unfair trade practices in the auto insurance industry.

During the recent debate over no-fault, trial lawyers and some witnesses who testified on the council legislation maintained that some accident victims had trouble collecting from their insurance companies under no-fault, which entitles motorists to collect medical expenses from their insurance companies regardless of who is at fault.

"Citizens have reported numerous instances of being treated unfairly by their insurance companies," said Ray.

" . . . It is becoming clear that these are not isolated cases, but part of an industrywide pattern which must be put to an end," he said.

Although neither Ray nor the trial lawyers could provide statistics on abuses that they claim have become a major problem, Ray plans to use his hearings to gather such data. He hasn't set a date yet for the hearings.

Knight said that Geico welcomes any legislation aimed at establishing "a consumer-oriented standard of conduct" for insurance companies.

"Our experience elsewhere over the years has been that from time to time there will be a poorly managed company that inadvertently or due to inefficiencies will fail to pay claims on time," said Knight. "I certainly don't see any harm in preventative legislation."

Meanwhile, regardless of what new information council members discover about no-fault insurance, some consumer groups are having some serious discussions about using a referendum to repeal the council's repeal of no-fault.