The new law, however, makes it illegal to use credit scores in underwriting auto insurance. Other bans, such as using education or occupation, remain administrative regulations.

Frank Mancini, president and chief executive of the Massachusetts Association of Insurance Agents, says the law supports his group's longstanding opinion about the use of the underwriting tool.

"It shouldn't be used," he says. "Study after study has shown that there can be so many mistakes in credit reports, and it's incredibly difficult to fix them."

The MAIA was campaigning to get a question on the ballot next year to ban credit scoring. With the signing of the law, the association has dropped the question.

Many within the insurance industry, including the American Insurance Association and the Property Casualty Insurers Association of America, have supported the use of credit scoring as a valuable tool.

"AIA supports the use of underwriting and rating tools that allow insurers to make informed decisions regarding risk," says Willem O. Rijksen, spokesman for the AIA. "The vast majority of policyholders benefit from lower premiums as a result of credit-based insurance scoring.  AIA opposed this legislation because it will prohibit the use of this beneficial tool and result in a disadvantage for Massachusetts drivers."