"We did not cause the financial crisis," said Michael Swenson, a managing director at the firm.
"There's things we wish we could have done better in hindsight, but at the times we made the decisions, I don't think we did anything wrong," he said.
Sparks said though he felt sympathy for Goldman clients who lost money, he said had no regrets.
"Regret to me means something that you feel you did wrong and I don't have that. What I do have though is -- we made mistakes in our business which I think any business does and we made some poor business decisions in hindsight," he said.
Levin later shot back: "You got no regrets? You ought to have plenty of regrets. I don't think you're willing to acknowledge them but you oughta have them. I don't think you will acknowledge them, that's why we have to do some regulation."
Today's hearing included testimony from Fabrice Tourre, the trader at the center of a civil fraud lawsuit filed by the Securities and Exchange Commission against Goldman Sachs earlier this month. Tourre, who described himself as "fabulous Fab" in a Goldman e-mail released by the SEC, was the only individual named as a defendant in the lawsuit.
Speaking publicly for the first time since the SEC charges were announced, Tourre asserted his innocence, insisting repeatedly to a Senate panel that he didn't mislead clients in a controversial mortgage derivative product the SEC claims was designed to fail. The SEC alleges that Goldman and Tourre failed to disclose to investors that hedge fund Paulson & Co. bet against the product after helping choose the mortgages that it was tied to.
"I deny -- categorically -- the SEC's allegation," Tourre said. "And I will defend myself in court against this false claim."
"The last week has been challenging for me and my family," he said, "as I have been the target of unfounded attacks on my character and motives. I appreciate the opportunity to appear before the Subcommittee to answer these false charges. I wish to repeat -- I did not mislead IKB or ACA, two of the most sophisticated institutional investors in these products anywhere in the world."
A number of e-mails from Tourre have been made public by Goldman Sachs itself and the Senate panel in recent days.
Asked about internal Goldman e-mails that reveal Tourre joking about selling bonds to "widows and orphans that I ran into at the airport" in Belgium, Tourre said, "I regret these e-mails. They reflect very bad on the firm and on myself and I think, you know, I wish I hadn't sent those."
Lawmakers said in their opening statements at today's hearing that while Goldman may not have committed a crime in betting against the same securities they were selling to investors, the bank's actions still seemed simply wrong.
"While such conflicts of interest may not be illegal," Collins said, "they certainly seem ethically questionable."
Sen. John McCain, R-Ariz., went a step further, saying, "There's no doubt their behavior was unethical and the American people will render a judgment as well as the courts."
A fiery Sen. Claire McCaskill said the Wall Street firm was simply gambling with the securities known as synthetic collateralized-debt obligations.
"It's gambling pure and simple," she said. "Raw gambling. They're called synthetic because there's nothing there."