Twenty years ago, on the morning of Sept. 11, Washington attorney Kenneth Feinberg was in Philadelphia teaching a law school class on mediating class-action lawsuits.

Feinberg, an old-school D.C. insider who was previously chief of staff for Sen. Edward M. Kennedy (D-Mass.), was one of the country’s foremost experts on such matters, having settled massive cases involving the use of Agent Orange in Vietnam and asbestos poisoning that sickened thousands.

After class wrapped up, Feinberg saw students huddled around a TV in a hallway. He wandered over. A plane had flown into the World Trade Center. An accident, Feinberg thought. Minutes later, the second plane hit the towers. Then another slammed into the Pentagon.

So many lives lost, so many changed forever — including Feinberg’s.

Two months after the terrorist attacks, Feinberg was handed an unthinkable task by Congress: assigning dollar values to the 3,000 lives lost that day, as well as the thousands injured. As special master of the September 11th Victim Compensation Fund, Feinberg presided over an unprecedented, unlimited budget to repay families what could never be repaid.

There was no syllabus on how to do that.

“What’s a fair amount for a body?” said Feinberg, now 75, during an interview at his law practice in the Willard Office Building, just down the street from the White House. “It’s not justice. It’s not fairness. It can’t be fairness. It’s mercy.”

The nearly three years Feinberg and his office administrator Camille Biros spent distributing more than $7 billion to 5,562 people is depicted in “Worth,” a new Netflix film that premiered this past Friday. With backing from former President Barack Obama’s production company, the movie stars Michael Keaton as Feinberg, Amy Ryan as Biros and Stanley Tucci as Charles Wolf, a New York man whose wife was killed in the attacks and who later protested Feinberg’s oversight.

The movie, Feinberg said, is a fairly accurate representation of what happened, including his own evolution from a by-the-books attorney to “a rabbi and a priest and a nun,” as he put it.

“There’s a certain dramatic license that they play in the film,” said Feinberg, a father of three adult children who lives in Bethesda with his wife, Diane. “But I must say that the emotion was overwhelming.”

Feinberg asked for it.

Born in a working-class town south of Boston, Feinberg attended the University of Massachusetts, where he fell in love with two things — American history and theater. He played the Duke of Venice in “Othello,” among other roles.

He even toyed with a career in acting, but his dad, a tire store owner, talked him out of it.

“Ken, most actors end up waiting tables in New York City and starving,” Feinberg recalled his father saying in his autobiography. “Why not take your acting talents to law school? You can play Hamlet in front of juries."

After law school at New York University, Feinberg became a law clerk and then a federal prosecutor in Manhattan. In 1975, he landed a job as counsel to Kennedy on the Judiciary Committee, where he helped craft the Foreign Intelligence Surveillance Act. Feinberg later rose to become Kennedy’s chief of staff.

In 1983, his career turned away from politics. A federal judge in New York asked him to mediate a lawsuit filed by Vietnam veterans against the chemical industry over Agent Orange, a “tactical herbicide” used by the U.S. military during the war that left thousands of service members sick.

Feinberg had no training in mediation, but he did have a booming Boston voice and a natural ability to lean in very close to people and help them narrow their differences enough so that both sides thought they were agreeing to something that resembled something like fairness.

More cases followed: breast implants, heart valves, asbestos.

But nothing would prepare him for the aftermath of Sept 11.

After reading about the plan to appoint a special master in the newspaper, Feinberg thought he’d be perfect for the job — one that he would do pro bono. He called an old friend, then-Sen. Chuck Hagel (R-Neb.), to express his interest. That led to two interviews with Attorney General John Ashcroft during which they discussed the parameters of the job, which essentially allowed the administrator wide discretion over who got what from a bottomless bag of funds.

Feinberg got the job.

He and Biros came up with a formula for compensation based on current and future income with the goal of making sure that 85 percent of the funds weren’t paid to the highest income-earners, including wealthy financial executives at brokerage firms, including Cantor Fitzgerald, which lost more than 650 workers at the World Trade Center.

Few people were happy with Feinberg. He had tense encounters with victims’ families at town hall meetings. Many harangued him not just for his formula but also the coldness with which he explained it. Wolf, whose wife, Katherine, was killed in the towers, organized critics of Feinberg and set up a website called fixthefund.org.

On the site, in his “statement of purpose,” Wolf wrote:

Ken Feinberg is everything the Founding Fathers of this country were striving to avoid when they wrote the Constitution. With a sparsely written law, Feinberg was forced to write most of the details himself in the form of regulations. Then, he has to implement what he just wrote, pointing back to those same regulations as unbendable rules. Finally, he is the final adjudicator as the law prohibits judicial review by the courts. Feinberg has the power of King George III; he is lawmaker, administrator, judge and jury.

“Nobody really felt like he was listening to us,” Wolf said in an interview.

And sign-ups were lagging — a problem because the fund was inspired by a desire to get victims to accept the payments and waive the right to sue the airlines, sparing the airline industry from collapsing under thousands of lawsuits.

But Feinberg and Biros plodded on, meeting individually with families to hear their stories — hundreds of meetings, day after day. The families of busboys. The families of bond traders. The stories were harrowing: a firefighter killed by a flying body, a man burned on 85 percent of his body after being trapped in an elevator.

The burned man showed up to Feinberg’s office with a team of doctors.

“Singed, no eye brows, no hair at all,” Feinberg remembered. “Artificial skin.”

“It was horrible,” Biros said.

There was nothing requiring him to come in for the meeting.

“But he wanted to be heard,” Biros said. “He wanted people to know what happened to him.”

As the process wore on, Wolf noticed a change in Feinberg.

“It was like God came down and talked to Ken,” Wolf said.

There was more empathy from Feinberg, Wolf said, more willingness to adjust awards beyond what the formula called for.

The process wrecked Feinberg, Biros and the firm’s lawyers.

“You cry in private, never professionally in front of the families,” Feinberg said. “And then you’re up all night. What do we do with this one? What about this? What about them? And it’s just debilitating.”

Even after finishing the disbursements for the 9/11 attacks, Feinberg and Biros were not finished.

Feinberg’s firm became the go-to law firm to administer compensatory funds following other tragedies. The mass shootings at Virginia Tech University, Sandy Hook Elementary School in Connecticut and the movie theater in Aurora, Colo. The 2010 BP oil spill. Victims of clergy sexual abuse.

Feinberg no longer seeks these tragedies; they find him.

“If it’s on the front page,” Feinberg said, “we just know we’re going to get that call.”

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