California's insurance regulator last unveiled new regulations to prevent brokers from taking secret commissions to steer customers to certain policies.
California's new rules would require agents and brokers to disclose any compensation and commission fees they stand to receive for selling an insurance product.
Violators would be fined up to $10,000 per incident and could suffer loss or suspension of a licence.
The new California rules come less than a week after New York Attorney General Eliot Spitzer announced he was suing the world's largest insurance broker, Marsh & McLennan Cos., for rigging bids and price-fixing.
The investigation has expanded to include many different kinds of insurance in a number of states. California Insurance Commissioner John Garamendi said his office probably would unveil lawsuits next week.
"We are in the opening pages of what is going to be a very long and sordid story," Mr Garamendi told a news conference in Sacramento. "Where it leads us we do not know. This is going to be a long, long unhappy situation for the insurance industry."
Marsh & McLennan, the target of Mr Spitzer's suit, disclosed last night it was renegotiating terms of $2.8 billion in backup bank financing. The move is likely to raise borrowing costs at a time Marsh is also losing business-placement fees and facing customer attrition and higher compliance costs.