The Marsh executive asked the insurance company in an e-mail message to send someone to a meeting to pretend to make a bid for an insurance policy being sought by a customer - even though Marsh had already decided to steer the business to another insurer that agreed to pay a kickback to Marsh.

The e-mail message - written in 2001 and disclosed last week as part of a New York State lawsuit asserting that Marsh Inc., a unit of Marsh & McLennan, cheated customers - even made a joke about creating an illusion of competition.

"This month's recipient of our Coordinator of the Month Award requests a body at the rescheduled April 23 meeting," wrote the Marsh executive, whose name was blacked out in the released documents. "He just needs a live body. Anyone from New York office would do. Given recent activities, perhaps you can send someone from your janitorial staff - preferably a recent hire from the U.S. Postal Service."

The manager from the other company, whose name had also been blacked out in the documents, evidently did not find bid rigging quite so funny.

In all capital letters, he responded, "We don't have the staff to attend meeting just for the sake of being a 'body.' While you may need 'a live body,' we need a 'live opportunity.' We'll take a pass."

The e-mail exchange is one of numerous potentially embarrassing communications that were disclosed by Eliot Spitzer, the New York State attorney general, who used similarly damaging e-mail messages to help press his successful conflict-of-interest investigation of Wall Street analysts two years ago. The accusations against Marsh also assert there was a conflict of interest in its role as a broker.

Marsh is supposed to help its customers find the most complete insurance coverage at the best possible price. In reality, the lawsuit contends, Marsh directed business toward insurance companies that paid it kickbacks, while using sham bids from other insurers to create the illusion of competition. As a result, the suit says, the customers ended up paying more than they should have.

The latest foray by Mr. Spitzer, who said that his investigation into what he called "widespread corruption" was still in its early stages, is already getting results. In the wake of the lawsuit, Marsh said on Friday that it would immediately stop the longstanding practice of accepting the lucrative payments, which the industry calls incentive fees but critics contend are kickbacks. Marsh received $800 million in incentive fee payments in 2003.

In addition to the civil suit against Marsh, two executives at the American International Group, one of the world's largest insurers, and a manager at Ace Ltd., another big insurer, pleaded guilty last week to criminal charges for helping Marsh rig bids. All three executives are cooperating with investigators.

In a statement last week after the lawsuit was announced, Marsh said that it was cooperating with the state investigation. "Marsh is committed to servicing its clients to the highest professional and ethical standards," the company said. Marsh's stock has fallen sharply since the suit was filed on Thursday. The shares fell to $29.20 a share, down $5.65, on the New York Stock Exchange on Friday, after plunging $11.28 a share on Thursday, for a two-day decline of 37 percent.

Maurice R. Greenberg, the chief executive of A.I.G., said in a conference call on Friday that it was likely that his company would also stop making incentive payments to brokers. A.I.G. shares fell $2.15, or 3.6 percent, to $57.85 on the Big Board on Friday.

Ace said yesterday that it also would no longer pay brokers' fees known as placement service agreements, or P.S.A.'s, for steering business toward the company. "Therefore, effective immediately, we will discontinue all P.S.A.'s throughout our organization," Evan G. Greenberg, Ace's chief executive, said in an employee letter posted on the company's Web site. "We will continue to cooperate fully" with New York's attorney general, he said.