Adam Mosseri, the head of Instagram, has agreed for the first time to testify before Congress, as bipartisan anger mounts over harms to young people from the app.

Mr. Mosseri is expected to appear before a Senate panel during the week of Dec. 6 as part of a series of hearings on protecting children online, said Senator Richard Blumenthal, who will lead the hearing.

Mr. Mosseri’s appearance follows hearings this year with Antigone Davis, the global head of safety for Meta, the parent company of Instagram and Facebook, and with Frances Haugen, a former employee turned whistle-blower. Ms. Haugen’s revelations about the social networking company, particularly those about Facebook and Instagram’s research into its effects on some teenagers and young girls, have spurred criticism, inquiries from politicians and investigations from regulators.

In September, Ms. Davis told Congress that the company disputed the premise that Instagram was harmful for teenagers and noted that the leaked research did not have causal data. But after Ms. Haugen’s testimony last month, Mr. Blumenthal, a Connecticut Democrat, wrote a letter to Mark Zuckerberg, the chief executive of Meta, suggesting that his company had “provided false or inaccurate testimony to me regarding attempts to internally conceal its research.”

Mr. Blumenthal asked that Mr. Zuckerberg or Mr. Mosseri testify in front of the consumer protection subcommittee of the Senate’s Commerce Committee to set the record straight.

“He’s the top guy at Instagram, and the whole nation is asking about why Instagram and other tech platforms have created so much danger and damage by driving toxic content to children with these immensely powerful algorithms,” said Mr. Blumenthal, who chairs the subcommittee. “The hearing will be critically significant in guiding us to develop laws that can have an impact on making platforms safer.”

Dani Lever, a Meta spokeswoman, said in a statement: “We continue to work with the committee to find a date for Adam to testify on the important steps Instagram is taking.”

Mr. Blumenthal said he would question Mr. Mosseri about how Instagram’s algorithms can send children into dangerous rabbit holes. Since Mr. Blumenthal’s subcommittee began its series of hearings, lawmakers have heard from hundreds of parents and children who have shared personal anecdotes, including stories of how posts on fitness devolved into recommendations for content related to extreme dieting, eating disorders and self-harm.

Mr. Blumenthal said he would seek a commitment from Mr. Mosseri to make Instagram’s ranking and recommendation decisions transparent to the public and to experts who can study how the app amplifies harmful content. Mr. Blumenthal said that executives at Snap, TikTok and YouTube, who all testified in a previous hearing, have committed to algorithmic transparency.

While Mr. Zuckerberg has become accustomed to being hauled in front of U.S. lawmakers, this will be the first time Mr. Mosseri will testify to them under oath. A trusted lieutenant to Mr. Zuckerberg who was chosen to lead Instagram in 2018, Mr. Mosseri has become the photo-sharing app’s public face, hosting regular video announcements about new features and appearing on morning television shows.

In September, before Ms. Davis’s Senate hearing, Mr. Mosseri appeared on NBC’s Today Show to announce that Instagram would pause the development of a version of the app designed for children following public backlash and renewed lawmaker interest sparked by Ms. Haugen’s leaks. BuzzFeed News first reported in March that the company was working on a version of Instagram for children under 13.

Mr. Mosseri’s scheduled appearance is the latest fallout from Ms. Haugen’s leaked files, which were first reported by The Wall Street Journal. Those documents, called The Facebook Papers, have formed the basis for multiple complaints to the Securities and Exchange Commission that Meta misled investors about its efforts to protect users.

Last week, a bipartisan group of 11 state attorneys general announced that it had opened an investigation into whether Meta had failed to protect the mental well-being of young people on its platforms including Instagram.

This article is part of the On Tech newsletter. Here is a collection of past columns.

U.S. government technology has a mostly deserved reputation for being expensive and awful.

Computer systems sometimes operate with Sputnik-era software. A Pentagon project to modernize military technology has little to show after five years. During the coronavirus pandemic, millions of Americans struggled to get government help like unemployment insurance, vaccine appointments and food stamps because of red tape, inflexible technology and other problems.

Whether you believe that the government should be more involved in Americans’ lives or less, taxpayers deserve good value for the technology we pay for. And we often don’t get it. It’s part of Robin Carnahan’s job to take on this problem.

A former secretary of state for Missouri and a government tech consultant, Carnahan had been one of my guides to how public sector technology could work better. Then in June, she was confirmed as the administrator of the General Services Administration, the agency that oversees government acquisitions, including of technology.

Carnahan said that she and other Biden administration officials wanted technology used for fighting wars or filing taxes to be as efficient as our favorite app.

“Bad technology sinks good policy,” Carnahan told me. “We’re on a mission to make government tech more user-friendly and be smarter about how we buy it and use it.”

Carnahan highlighted three areas she wanted to address: First, change the process for government agencies to buy technology to recognize that tech requires constant updates. Second, simplify the technology for people using government services. And third, make it more appealing for people with tech expertise to work for the government, even temporarily.

All of that is easier said than done, of course. People in government have promised similar changes before, and it’s not a quick fix. Technology dysfunction is also often a symptom of poor policies.

But in Carnahan’s view, one way to build faith in government is to prove that it can be competent. And technology is an essential area to show that.

Building that competence starts with something very dull — budgeting and procurement. Carnahan told me last year that governments tended to fund digital infrastructure the way they did bridges. They buy it once and try not to think about it much for the next few decades. That mentality is a mismatch with technology, which works best with constant improvements and upkeep.

Carnahan said that she was trying to spread the message in Congress and government agencies that a predictable amount of government funding doled out over time is a better approach to buying tech. Carnahan said the government should think of tech like Lego sets, with pieces that are regularly swapped out or rebuilt. (Hey, the metaphors work for me.)

She also hopes to use technology to help remove headaches that make it difficult for people to have access to public services.

As one example, Carnahan mentioned that she wanted to significantly expand the number of government services accessible through login.gov. There, people can create a single digital account to interact with multiple services, like those for applying to a government job or filing for disaster help for a small business.

And like many people in government, Carnahan is also making a pitch for people with technical expertise to work for the public sector. Her appeal is part pragmatism and part patriotism. “Government is the single best way to have an impact on people’s lives,” Carnahan said.

She said that remote work had also made government jobs more realistic for people who don’t want to move to Washington, and so have programs like the U.S. Digital Service and the new U.S. Digital Corps, which allow technologists to work short stints alongside civil servants.

Carnahan isn’t pretending that changing decades of relative dysfunction in government technology will be easy. But she believes doing so is crucial now that technology is often the primary way people interact with local, state and federal governments, whether it’s registering to vote or getting help with a Medicare claim.

“Making the damn websites work is the fundamental thing that people expect out of government these days,” she said.

Before we go …

• How do we keep children safe online? U.S. law more or less bans internet services from having users who are younger than 13. My colleagues at New York Times Opinion talked to young kids who are online despite the restrictions, and made the case that the U.S. learn from new child-protection guidelines in Britain.

  (There’s a back story about those clever kids in the Opinion Today newsletter. You can sign up here.)

• A hammer falls on spyware: Apple sued NSO Group, an Israeli company whose software has been abused by governments to spy on the smartphones of human rights activists, journalists and dissidents. My colleague Nicole Perlroth writes that the lawsuit and the U.S. government’s recent blacklisting of NSO could be steps toward more oversight of the global market for spyware.

• Thoughtful gift ideas! Brian X. Chen, the consumer technology columnist for The Times, has lovely ideas for tech-related holiday presents that are not gadgets. (I bet Brian’s wife is going to love her digital photography lesson. Don’t spoil the surprise.)

Hugs to this

I’m obsessed with the NASA spacecraft that launched today on a mission to smack into an asteroid the size of a sports stadium to knock it off course. Yes, this is a little like the plot of the movie “Armageddon.”

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