Pitt, who was appointed to lead the SEC by President George W. Bush in 2001, oversaw the closure of financial markets in the wake of the September 11, 2001 attacks. He had previously been a staff attorney and general counsel, among other roles, at the agency and received the SEC's award for distinguished service in 1977, a year before leaving the agency.

"It was one of his greatest dreams to come back later in his career to chair the agency," the five current members of the SEC Commission said in a statement.

He resigned and left the agency again in 2003, under fire over his appointment of a former FBI chief embroiled in an accounting scandal to run the then-newly created Public Company Accounting Oversight Board. The accounting watchdog was created after the failures of WorldCom and Enron to restore investor confidence.

At the time, fellow SEC Commissioner Roel Campos said: "There has certainly never been anyone who loved this agency more than Chairman Pitt."

In a 2005 interview with the San Francisco Chronicle, Pitt attributed his exit to the politicization of the agency after the Enron scandal and highlighted the work the commission had done to adopt new regulations under the 2002 Sarbanes-Oxley Act.

Pitt was a graduate of St. John's University School of Law and the City University of New York, according to the SEC's website. He taught at various points at Georgetown University and the University of Pennsylvania.

Most recently, Pitt founded and led consulting and law firm Kalorama Partners in Washington. He passed away on Tuesday, according to the statement from Jane Cobb, executive director of the SEC Historical Society.

He was 78.

"Over the years, Harvey has been extremely generous with his time and sage advice," said Michael Piwowar, a former SEC commissioner.