Shannon Liss-Riordan won millions for workers. But some fault her earnings from client cases.

Shannon Liss-Riordan in her office.Suzanne Kreiter/Globe Staff

In the Democratic race for attorney general, Shannon Liss-Riordan has presented herself as a champion of working people, a class-action employment lawyer who has put millions of dollars back in the pockets of waitresses, truck drivers, janitors, and other undervalued employees she has represented in court.

But the prolific attorney was also faulted, well before her foray into politics, for seeking substantial shares of those lucrative settlements, a criticism that goes straight to the heart of her campaign as a tireless defender of low-wage workers.

In 2016, US District Judge Edward M. Chen threw out her $100 million settlement with Uber as “not fair, adequate, and reasonable,” saying it wasn’t a good enough deal for the drivers, some of whom had publicly blasted her for seeking $25 million in legal fees.

Douglas O’Connor, the original complainant, accused Liss-Riordan of selling drivers out, while Hunter Shkolnik, a lawyer representing other Uber drivers who objected to the settlement, said she had “single-handedly stuck a knife in the back of every Uber driver in the country.”

Liss-Riordan said that only about 30 of the nearly 400,000 drivers objected to the proposed settlement. And despite the competing interests cited by lawyers, “the court had certified the case as a class action and agreed with me that they shared a common interest,” she said.

Liss-Riordan attributed the rancor in the case to the interest generated when “there’s a high-profile case and there’s a lot of dollars at stake.”

Liss-Riordan’s advocacy for workers — and her political image as the architect of legal challenges to the gig economy — have emerged as key factors in the primary campaign for attorney general. In a debate earlier this month, Liss-Riordan suggested the position would be a “continuation of the work I have been doing as a private attorney general for years.”

“This is the job I was made for,” said Liss-Riordan, who is 53 and lives in Brookline.

But her opponents, former Boston city councilor and mayoral candidate Andrea Campbell and former assistant attorney general Quentin Palfrey, have challenged her legal awards and suggested her campaign is reliant on the proceeds of exorbitant legal settlements. Liss-Riordan has poured $3 million of her own money into her campaign, which she has estimated could cost as much as $12 million.

To Liss-Riordan, who has a record of winning high-stakes cases on behalf of low-wage workers, the line of attack is familiar, a political strategy since former vice president Dan Quayle blasted trial lawyers in the 1990s.

“I mean, I’m a trial lawyer. That is what I do,” she said. “I represent people who need their voices heard and who would not be able to hire a lawyer otherwise.”

Faced with the blowback to her proposed Uber settlement in 2016, however, she offered to reduce her fee request by $10 million.

Liss-Riordan, who said she is “widely recognized as one of the top employment lawyers” in the country, burst onto the scene in the early 2000s, filing at least 40 lawsuits on behalf of waiters, bartenders, Starbucks baristas, and even strippers, alleging they were being cheated out of tips in the workplace. Dubbed an “avenging angel for workers” in an early Boston Globe story, Liss-Riordan was the first to take aim at the business model of the gig economy, arguing that drivers for ride-hailing companies Uber and Lyft were misclassified as independent contractors and deserved the workplace rights of employees.

But Uber and Lyft prevailed on that point: Drivers are still not employees. And her proposed settlements were derailed not only by driver complaints but by a California appeals court ruling that bound many of the plaintiffs to an arbitration clause in their contract.

In the Uber case, that dissolved the class of nearly 400,000 that Liss-Riordan was representing and left hundreds of thousands of drivers with nothing.

The revised Uber settlement covered far fewer drivers — about 11,000 in California and 2,600 in Massachusetts — but at $20 million, offered a more generous payment of about $2,200 per driver, on average. Liss-Riordan still received 25 percent of the settlement: $5 million.

At the same time she was fending off Uber drivers’ criticism, Liss-Riordan’s proposed settlement with Lyft drivers was rejected on similar grounds. In a nearby California courtroom, US District Judge Vince Chhabria rejected her proposed $12.25 million settlement with Lyft, saying the calculations used to estimate the value of the suit were too low and shortchanged drivers.

“And so I wonder if you’re now in a position of having to explain why a settlement of $12 million, 30 percent of which you propose to go to the lawyers, is a reasonable settlement,” Chhabria asked, “given the true maximum value of the lawsuit, which is somewhere in the neighborhood of $170 million.”

Under the proposed Lyft settlement, drivers would be paid based on their estimated miles driven, an average of only $142, while Liss-Riordan made $800 an hour. At that rate, she would have had to work just 11 minutes to make the same amount from the settlement as the average driver.

Ultimately, Lyft settled with the drivers for $27 million, only $3.65 million of which went to Liss-Riordan.

Attorneys in class-action cases generally receive around 25 percent of the settlement said Marsha Kazarosian, a past president of the Massachusetts Bar Association. The high fees reflect the inherent risk a lawyer takes in accepting a complicated case with multiple plaintiffs on contingency fees. If they don’t win, they don’t get paid at all.

“There are plenty of cases that I have devoted years to — 10 years, 15 years — and not made a penny off because we were unsuccessful,” Liss-Riordan said. “On the other side of it, the white-shoe corporate defense firms, they get paid either way, win or lose.“

Contingency fees allow people of average means to pursue claims against corporations, Kazarosian said. Still, Kazarosian was struck by the rate Liss-Riordan commands. In the most recent case against Uber in California, Liss-Riordan is seeking $950 an hour, according to court records.

In class-action cases, the lawyer’s hourly rate and final share of the settlement must be approved by a judge, who sometimes demands revisions.

“It is not at all uncommon for judges to reject settlements, either because the fee request is too high or because of something having to do with the settlement itself,” noted Charles Silver, a University of Texas Law professor who focuses on aggregate lawsuits and attorneys’ fees. He pointed to the twice-rejected settlement between the National Football League and players over concussions.

“Then, there was a big fight over attorney’s fees, too,” Silver said. “There’s just nothing at all unusual about either of these two things.”

After the settlement, Uber, along with Lyft, DoorDash, and other gig-worker companies, went on to spend $200 million persuading California voters to retain their drivers’ status as independent contractors.

A similar ballot question was expected on the Massachusetts election ballot this November, but it was rejected by the Supreme Judicial Court. Liss-Riordan led the Coalition to Protect Workers’ Rights, a labor-backed group formed to oppose the effort. Liss-Riordan said that as attorney general, she will continue “the fight that I’ve been in now for more than a decade to get these workers properly classified and get their employment rights.”