WASHINGTON — Beleaguered Wall Street powerhouse Goldman Sachs Group switched to offense yesterday, contending that the $13 billion from bailed-out American International Group was fully justified and in fact was good for taxpayers.

But that did little to quell the criticism that Goldman and other financial institutions should have taken less than they were owed on insurance for their risky bets on the subprime housing market.

Goldman Chief Financial Officer David Viniar said his company simply was trying to protect its shareholders — which now include taxpayers after the company received $10 billion in financial rescue money last fall.

"If we had taken a discount, then we would have taken a loss to Goldman Sachs," Viniar said in a conference call with reporters convened by the company to address its involvement with AIG. "We also have taxpayer money at Goldman Sachs, and it's part of our responsibility to protect that money and not lose it."

But some lawmakers and others argued that holders of the insurance should have been forced to take less than 100 percent — a haircut in Wall Street parlance — because they would have gotten much less if AIG had been allowed to slip into bankruptcy.

"If you invest in GM, you're asked to take a huge haircut," said Rep. Brad Sherman, D-Calif.

Sherman noted that terms of the federal bailout of General Motors required it to renegotiate deals with company bondholders. "But those who put their money in the AIG casino are told that you will be paid in full at the cost of the federal government," he said.

Goldman received $13 billion — more than any other financial institution — in payment for AIG investment guarantees after the federal government stepped in with bailout commitments that now total as much as $172 billion to keep the insurance giant from failing.

Following the outrage over $165 million in retention bonuses, AIG this week disclosed the names of dozens of banks and other institutions that it had paid last year after being bailed out by the Federal Reserve and Treasury Department.

Sherman said Goldman should return the $13 billion it received from AIG to the U.S. Treasury.

"And it may well be that if Goldman can't repay that money, that the best thing for the country is for Goldman to be in receivership," he said.

Details of the AIG payments have sparked sharp criticism from Sherman and other lawmakers, who complained that companies that helped cause the financial crisis should not have received full payment of their collateralized debt obligations from AIG with the help of taxpayer funds.

AIG tried before and after the bailout to get Goldman to take a discount on the money it was owed, Viniar said. Goldman consistently refused.

"We had ongoing negotiations with AIG, and they would periodically say to us ... we'd like to settle this for less than we thought they owed us, and our answer would always be no," Viniar said. "It's kind of what we do in most of our transactions. If people want to settle for less than we think we're due, we say no."

But some in Congress think that's exactly what Goldman and other companies should have done given that taxpayer money helped save their investment insurance from AIG.

Criticism of Goldman has come from both sides of the political spectrum. Former House Speaker Newt Gingrigh, a Republican, and former New York Attorney General Elliot Spitzer, a Democrat, blasted Goldman and other companies for being made whole on their AIG exposure at taxpayer expense.

And there is growing sentiment that the full payments by AIG to Goldman and other large financial institutions, including Bank of America, Citigroup, Barclays and Deutsche Bank, are a bigger outrage than the bonuses because so much more money is involved.

"What I want to know is why more people aren't paying attention to the fact that some other banks were being paid 100 cents on the dollar as counterparties," Sen. Christopher Dodd, D-Conn., said yesterday. AIG "had the opportunity to do less than that. The question is: Why didn't they?"

The answer isn't so simple, said Chris MacDonald, a business ethicist at Saint Mary's University in Canada who has followed the AIG issue. While protecting shareholders is paramount for company executives, the calculations can be different in a time of national crisis.

"The managers of Goldman Sachs need to make sure their shareholders are treated fairly and arguably should be asking for full payment," he said. "But there's nothing to say that AIG and the federal government shouldn't say, "You should accept 80 cents on the dollar, or 50 cents on the dollar.