Ace has announced sweeping changes in the way its underwriters deal with brokers in response to the Spitzer inquiry. It has also fired two executives and suspended three other directors.

The insurer has issued new, detailed guidelines relating to the way it works with brokers and submits quotes. These include a requirement that any commissions paid to brokers be "reported to policyholders on the declarations page of all commercial policies". Ace has already terminated all contingent commission payments to brokers.

The insurer will also appoint a business practices compliance officer. An outside consulting firm is being retained to review the insurer's business practice, training, compliance and controls.

Peter Mear, the company's general counsel, will become the chief ethics officer and head of the Ace ethics committee.

President and chief executive of Ace Evan Greenberg said: "These new business practice compliance programmes will support and strengthen our companywide commitment to ethical conduct.

"Our internal investigation is ongoing, and we will continue to look for further ways to enhance our business culture."

Ace also sacked two employees and suspended three others as a result of the ongoing investigation into improper business practices.

The "terminated" employees are Geoffrey Gregory, president, Ace Casualty Risk, and Patricia Abrams, an employee in that business unit.

The three suspended employees worked in Ace Casualty Risk on a team within the excess casualty unit that did business principally with Marsh Global Broking, the company added.

Ace said in a statement: "These personnel decisions result from past improper actions in the excess casualty unit of Ace Casualty Risk, managerial issues, and/or failure to cooperate with the company's internal investigation or the attorney general's investigation.

"Patricia Abrams has previously pled guilty to a criminal misdemeanor in connection with these actions."

Ace's investigation, which is continuing, is being conducted by the law firm of Debevoise & Plimpton LLP, under the direction of former US attorney Mary Jo White.