The SEC is deep in the midst of beating itself up over its failure over many years to catch Bernard Madoff's alleged $50 billion Ponzi scheme. Just yesterday, agency chair Mary Schapiro told Congress in a letter that "there needs to be a full accounting, both of Mr. Madoff's activities and why we did not detect the fraud, which we regret."

But is it in danger of making the same mistakes the second time around as the first?

The SEC's civil case against Madoff, hurriedly filed in December 2008 after Madoff allegedly confessed to his lawyer, is being conducted out of the agency's New York regional office, where Madoff's business was based. But it was the New York office that conducted the 2006 inquiry into Madoff that famously came up dry. That inquiry, which found only a few technical violations and recommended that Madoff register as an investment adviser, is now itself one focus of the investigation by the SEC's inspector general into how the agency failed to catch Madoff.

According to one former SEC enforcement veteran, in other cases where the agency opened a second investigation after a regional office was found to have slipped up the first time around, the second probe has sometimes been run out of the Washington headquarters, to ensure that it retains public confidence. That wasn't done here.

Asked about the matter by TPMmuckraker, an SEC spokesman declined to comment.

But there may be even less distance between the two Madoff investigations.

The current case is being led by Andrew Calamari, the Associate Regional Director for the New York office, who last month publicly called the Madoff case "a stunning fraud that appears to be of epic proportions." Calamari's name is listed prominently on the agency's civil complaint.

But Calamari appears tied to the ill-fated 2006 effort. Doria Bachenheimer, an Assistant Regional Director in the New York office "reviewed and approved" the decision to close that inquiry, according to a "Case Closing Recommendation" document obtained by the Wall Street Journal.

And an organizational chart produced by the agency in 2006, and obtained by TPMmuckraker, indicates that Calamari is Bachenheimer's supervisor. That reading of the chart was confirmed to TPMmucraker by the ex-SECer.

It's not clear that Calamari played any active role in the failed 2006 inquiry. But at the very least, the fact that he supervised the staffer who wrongly approved closing it -- and the fact that there's no evidence he raised red flags about her work -- might suggest he's not the ideal person to handle the followup, especially given the high public profile the case has taken on.

Calamari referred an inquiry from TPMmuckraker to the SEC's press office, which again declined to comment.