Westlaw, an online legal-research service, will sharply limit subscriber access to Social Security numbers in its database, a move announced after its top executives met Wednesday night with Sen. Charles Schumer, D.-N.Y., a sponsor of one of several bills before Congress addressing identity theft.

Schumer characterized Westlaw's action as a model for the rest of the data-brokerage industry. "This is a victory for consumers and a big loss for criminals who want to steal your Social Security number and your identity," Schumer said in a statement.

At congressional hearings earlier this week on identity theft, several lawmakers predicted Congress will pass a law to restrict the sale and dissemination of Social Security numbers. A 2003 study by the Federal Trade Commission estimates that identity theft costs Americans $5 billion a year.

In an E-mail message to InformationWeek, Peter Warwick, CEO of Westlaw publisher Thomson West, said events of the past months in which personal information was stolen from competitors' databases illustrates the importance of tougher controls. "The ultimate test for us as a business is to do the right thing," he said.

According to Schumer, Westlaw had eliminated access to 85% of its clients, mostly lawyers and government agencies--including the U.S. Senate. Westlaw no longer will sign contracts granting full access to Social Security numbers. Individual passwords will be given to law-enforcement officials deemed eligible to view full Social Security numbers.

Thomson West is a subsidiary of Thomson Corp., a media conglomerate with revenue of $8.1 billion last year.