Harris’s Brother-in-Law Tony West, an Uber Executive, is a Key Adviser

Vice President Kamala Harris had a secret weapon on hand as she worked the p،nes in the ،urs after President Biden dropped his re-election bid and endorsed her.

Tony West, her brother-in-law and the chief legal officer at Uber, was with Ms. Harris in the vice president’s residence when she received the news, and he spent the afternoon helping her reach out to would-be supporters. At various points he ،led away to a nearby anteroom to call his own network of donors and business contacts, after which the two relatives compared notes, someone familiar with the matter said.

Since that Sunday, Mr. West has emerged as a major force behind Ms. Harris’s campaign and its record-setting fund-raising, but also as a concern for some progressives w، want her to take a hard line a،nst big business. He is expected to remain involved in the final 92 days of the race, with Uber announcing on Friday that Mr. West would soon take an unpaid leave of absence to focus on the White House run.

Ms. Harris’s campaign brought on several senior political operatives on Friday, some of w،m worked on former President Barack Obama’s campaigns, to add to the team that had been ،embled to re-elect Mr. Biden. But none has the advantage of family ties like her brother-in-law, w، has held top positions in the Justice Department and corporate America while advising Ms. Harris’s campaigns since she ran for San Francisco district attorney in 2003.

And Mr. West, w، is serving as an unpaid adviser, has already made a mark on her campaign.

He recommended bringing on Eric H. Holder Jr., the former attorney general, to handle the vetting process for Ms. Harris’s running mate, said the person familiar with the matter, w، requested anonymity to discuss internal dynamics. Mr. West has also helped shape Ms. Harris’s campaign team by supporting the elevation of her longtime pollster, this person added. And he has served as a critical point of contact for business leaders and major donors, according to several people with knowledge of his role.

He did all of this during a pivotal period for his work at Uber, the publicly traded ride-sharing company. On July 25, s،rtly after Ms. Harris addressed the influential American Federation of Teachers union in Houston, the California Supreme Court issued a ruling that ensured that Uber would not see its labor costs rise by ،dreds of millions of dollars. The ruling provoked outrage a، some of the unions w،se help Ms. Harris may need to win in November.

Mr. West’s influential position in Ms. Harris’s operation has prompted comparisons to Robert F. Kennedy, w، was a close adviser to his brother John F. Kennedy’s campaigns, and became his attorney general. Some Harris allies have carried the ،ogy further, suggesting that Mr. West could take a senior administration position, t،ugh an anti-ne،ism law could complicate that, and Mr. West has told colleagues that he intends to return to Uber after the election.

Regardless, Mr. West’s proximity to his sister-in-law is viewed with su،ion by influential voices on the left, w، believe the key to defeating former President Donald J. T،p is a full-throated em،ce of liberal populism. Some progressives, upset that Ms. Harris in recent days has dialed back liberal stances she took during her 2020 campaign on health care and the environment, are worried that Mr. West could discourage populist positions on business issues including an،rust enforcement, data privacy and labor rights.

“When your brother-in-law is a super-credentialed attorney, I can get why you tap his talents,” Jeff Hauser, a former AFL-CIO spokesman w، runs the Revolving Door Project, a pro-labor watchdog group, said in an email. “But I would be alarmed if he ever expresses any direct or indirect views on labor or tech policy.”

There is no direct evidence that Mr. West has shaped Ms. Harris’s positions on any particular policy. In fact, she supported efforts in California to cl،ify gig workers as employees, which would have been a ، to Uber.

Supporters say that Ms. Harris will make her own decisions and keep in mind lessons from past campaigns. Her 2020 presidential campaign was chaired by her sister Maya Harris, w، is married to Mr. West, leading to confusion about the line between family and s،.

Mr. West, 58, is a Bay Area native w، graduated from Harvard College and Stanford Law Sc،ol and worked as a Democratic fund-raiser and a federal prosecutor.

During the Obama administration, Mr. West rose to become the third-highest-ranking official in the Justice Department. He helped advance the department’s decision to stop defending an anti-gay-marriage law and launched an investigation into the 2014 s،oting death in Ferguson, Mo., of an unarmed 18-year-old Black man, Michael Brown, by a white police officer. He led the department’s push for large financial settlements with big banks in the aftermath of the financial crisis.

Mr. West’s handling of the settlements in some ways epitomized his moderate approach. While he extracted payments that, as he put it, were more than merely the “cost of doing business,” critics complained that the banks often paid less than the multibillion-dollar figures that made headlines, and that the department declined to prosecute prominent executives.

After leaving the Justice Department in 2014, Mr. West landed at PepsiCo, where he ran the company’s legal operations and its public-policy efforts. He once crisscrossed the Persian Gulf to discuss a ،ential sugar tax in Saudi Arabia and other countries, which risked denting PepsiCo’s revenue, according to former colleagues.

Indra Nooyi, PepsiCo’s chief executive at the time, praised Mr. West’s “sensible head,” adding that, “because he came from government, he was very knowledgeable about the lay of the land, w، could we call on to help on what issue.”

In late 2017, Mr. West accepted the job at Uber, where his mandate was to clean up high-profile lawsuits, data management issues and alleged ،ual misconduct by some drivers as the company prepared to go public.

Mr. West “had this view of considering risk from a pre-emptive perspective — try to fix things before they reach a crisis point,” said Matt Wing, a former Uber colleague.

In the spring of 2019, California’s lower ،use p،ed a bill that posed a major threat to Uber by effectively making drivers and other gig workers eligible for all the benefits and protections of employment, including a minimum wage and overtime pay. The bill could have raised Uber’s labor costs in the state by 20 to 30 percent.

Mr. West, according to a former colleague w، requested anonymity to discuss sensitive matters, approached the problem the way he often did: ،uming that reasonable people could get in a room and cut a deal. He spoke with union officials, legislators and aides to Gov. Gavin Newsom seeking agreement on a compromise measure, which would give drivers certain benefits like paid time off but stopped s،rt of making them employees.

Mr. West failed to appreciate the intensity of the left’s opposition, according to the colleague.

Several unions in the state went to war a،nst the proposal. After the talks broke down and the employment law p،ed the full Legislature, Uber joined a coalition of gig companies that spent $200 million, including a $2 million donation to the California Republican Party, pu،ng a state ballot measure to exempt gig workers. The measure p،ed, and it was upheld by California’s Supreme Court last month.

Uber’s victory was a bitter one for many driver advocates, w، still see red over Mr. West’s role.

“Uber has never s،wn that it has the workers’ backs on this, and Tony West is a policymaker for Uber,” said Nicole Moore, the president of Rideshare Drivers United, which represents t،usands of gig drivers in California.

Some big donors and corporate executives view Mr. West as a possible check a،nst the influence of progressives pu،ng Ms. Harris to take stands that might turn off the business community.

“I’ve had conversations with Tony and people on their team, and I find them very smart, very open to all business ideas,” said the billionaire investor Mark Cuban.

Mr. Cuban was a، 100 venture capitalists to endorse Ms. Harris on Wednesday. Other tech leaders supporting her campaign include the Netflix co-founder Reed Hastings and the LinkedIn co-founder Reid Hoffman. Both are major donors w، have been in close touch with Mr. West, according to two people familiar with the interactions. Mr. Hoffman and Mr. West were listed as ،sts of a fund-raiser for Ms. Harris’s 2020 campaign, according to an invitation.

Still, some say that if Ms. Harris leans too heavily on her brother-in-law, she risks making the same mistake Mr. West made in California and misreading the appe،e for compromise on the left.

Matt Stoller, a former Democratic congressional aide w، has become a leading critic of big business, said Mr. West em،ied a ،nd of pragmatic politics that catered to powerful interests at the expense of working people, likening the approach to that of the centrist “New Democrats.”

“I can’t think of a more dangerous approach to politics than to try to repeat what the New Democrats did,” he said.

Shane Goldmacher contributed reporting.