Harvey Pitt, a authorized wunderkind who lasted simply 18 months as chairman of the Securities and Alternate Fee underneath President George W. Bush, died on Tuesday in Washington. He was 78.

His loss of life, in a hospital, got here after a sudden sickness, in accordance with his household, which didn’t specify the ailment.

Mr. Pitt’s profession had three consecutive legs, any one in every of which alone may need been the head on a lesser résumé. He started his profession on the S.E.C. and was promoted to basic counsel at age 30, the youngest ever to attain that rank. After solely three years, he left to symbolize company purchasers for the highly effective regulation agency Fried Frank. There, rising to managing accomplice within the agency’s Washington workplace, he helped it turn out to be massively worthwhile.

He returned to the S.E.C. as chairman in 2001, after crusing via a unanimous affirmation vote wherein Sen. Charles Schumer, Democrat of New York, referred to as him “the Zeus of the sector.” Not lengthy after, Mr. Pitt turned considerably of a family identify for overseeing the swift reopening of U.S. inventory exchanges after the assaults of Sept. 11, 2001.

His reputation dipped, nevertheless, amid a collection of company accounting scandals — most famously on the power large Enron — that drew renewed consideration to his prior company work. Representatives of each events questioned his curiosity in investigating private-sector wrongdoing.

The ultimate straw got here when it emerged that he had failed to inform the White Home or his fellow S.E.C. commissioners that an accounting board chairman he championed had headed the audit committee of an organization accused of fraud. Beneath stress, Mr. Pitt resigned on election evening 2002.

Born on Feb. 28, 1945 in Brooklyn, Harvey Lloyd Pitt was the kid of Morris and Sara Pitt. His father was a vice chairman of the Waldbaum’s grocery store chain; his mom was a homemaker.

Harvey, a Brooklyn Dodgers fan who was gutted when the staff left for the West Coast, his household stated, went on to earn levels from Brooklyn Faculty and St. John’s College earlier than becoming a member of the S.E.C. straight out of school. It was the one job he had ever wished.

In 1978, with a rising household, he went into personal apply, the place he represented a number of the similar individuals his group had been charged with regulating. His purchasers included Ivan Boesky, who pleaded responsible to insider buying and selling through the junk bond scandal of the late Nineteen Eighties, and scores of economic corporations.

Such was his fame that when Mr. Pitt’s personal agency landed in a minor authorized spat, his hiring of the then-smaller rival agency Williams & Connolly made waves.

“It was notable that if Harvey Pitt had confidence in us, others would simply observe, they usually did,” stated Brendan Sullivan, a Williams & Connolly senior accomplice.

At his affirmation listening to, Senator Phil Gramm, Republican of Texas, supplied a tweak on a music lyric from the British rock band Herman’s Hermits: “Harvey Pitt has seen it from either side.”

Contained in the fee, he was indefatigable, stated Cynthia Glassman, a former commissioner. After the group acquired Blackberry smartphones for the primary time, she stated, Mr. Pitt turned “massive on emails — particularly in the midst of the evening.”

He took a lighter method to S.E.C. enforcement than did his predecessors, telling Congress that he would “restore relationships which were harmed prior to now.” That perspective proved untenable within the wake of Enron and different scandals.

“Your alternative of phrases sends the fallacious message to auditors, to the S.E.C. workers and to the investing public,” Rep. John Dingell wrote to Mr. Pitt just a few weeks after Enron’s collapse.

Morale within the company dropped precipitously throughout Mr. Pitt’s tenure, and a slew of senior workers departed.

His fall in stature was summarized by a New York Occasions headline on the day in 2003 that his successor, William H. Donaldson, was confirmed: “S.E.C. Selection Says He’s No Harvey Pitt.”

However mates and former colleagues stated Mr. Pitt had been unjustly criticized. The previous S.E.C. basic counsel David Becker recalled being on the telephone with Mr. Pitt when the actual property developer Donald J. Trump referred to as to complain about Trump firms being investigated for fraud.

“Harvey politely defined that he was not able to assist, since he had added to the division’s proposal the very fraud allegation about which Trump was calling to complain,” Mr. Becker stated.

Mr. Pitt’s first marriage, to Phyllis Kay, led to divorce in 1981. He married Saree Ruffin in 1984. He’s survived by his spouse; two daughters, Emily Pitt and Sally Pitt Plowden; two sons, Jonathan and Rob; and three grandchildren.

Within the years that adopted his S.E.C. chairmanship, Mr. Pitt hardly receded from public view. He continued to weigh in on regulatory points, sometimes contributing opinion articles to The Wall Road Journal.

His most up-to-date column took a pointy view of recent proposed S.E.C. guidelines on personal funding funds.

“Too usually, regulatory calls for make it tough or not possible for brand new entrants to realize traction in an trade,” Mr. Pitt wrote. “There may be usually no voice on the desk representing the pursuits of that phase of the trade.”