LONDON — The “very future of democracy” is being threatened by “fake news,” a British parliamentary committee is warning, and the government response should include making tech companies legally liable and subject to algorithm audits.

That’s the conclusion after a lengthy probe by Britain’s Digital, Culture, Media and Sport Committee.

The plucky little panel, led by Conservative lawmaker Damian Collins, has covered issues including Facebook data mining, Russian election meddling and questionable Brexit financing. Witnesses who have testified before it — Christopher Wylie, Arron Banks and Alexander Nix, to name a few — have generated some of the biggest political stories of the year.

Its interim report was made available to news organizations, stakeholders, politicians and individuals for review before its official publication Sunday. After several British news organizations broke the embargo, The Washington Post decided to publish also.

The report concludes that an even bigger concern than obviously false information is the ma­nipu­la­tion and misuse of personal data and the deliberate stoking of fears and prejudices — by state-sponsored actors, private companies and other groups agendas — to influence voting.

In an interview with The Post last month, Collins said that after interviewing U.S. tech companies and researchers in Washington in February, the commitee realized that fake news based on lies was only a small part of the problem.

“One of the bigger areas, the much more difficult area, is the relentless targeting of people with hyper-partisan content that’s not necessarily fake, but it’s highly skewed to a particular point of view,” Collins said. “The issue there is: Do people understand why they are receiving this information? And also where is it coming from?”

He added, “One of the big issues with the Russian activities is it’s not just that they are doing it but they are masquerading as people in your country.”

Among the commitee’s recommendations are that the government should update electoral law to account for modern campaigning techniques, consider new restrictions for political advertising on social media and “establish clear legal liability for the tech companies to act against harmful and illegal content on their platforms.”

The report suggests that companies should be responsible for both “content that has been referred to them for takedown by their users, and other content that should have been easy for the tech companies to identify for themselves.”

It cites some free-speech concerns related to a German law that fines companies up to 50 million euros (almost $60 million) if they don’t remove hate speech from their sites within 24 hours. But the report also notes, “As a result of this law, one in six of Facebook’s moderators now works in Germany, which is practical evidence that legislation can work.”

The report also proposes that the government should have the power to audit tech companies’ nonfinancial aspects, including their algorithms.

In a statement, Facebook’s vice president of policy, Richard Allan, said, “We share their goal of ensuring that political advertising is fair and transparent and agree that electoral rule changes are needed.”

He noted that Facebook has already made advertising on its network more transparent and has been investing in people and technology to detect and remove bad content, but that it would go further still.

“We are working on ways to authenticate and label political ads in the UK and create an archive of those ads that anyone can search,” he said. “We will work closely with the UK Government and Electoral Commission as we develop these new transparency tools.”

Facebook founder Mark Zuckerberg has declined to testify before the committee, sending his chief technology officer and two policy staffers in his stead. Lawmakers have threatened to formally subpoena him when he next steps foot in Britain.

The wide-ranging report also highlights concerns over the funding of one of the campaigns that pushed for Britain to leave the European Union. “Arron Banks is believed to have donated £8.4m to the leave campaign, the largest political donation in British politics, but it is unclear from where he obtained that amount of money,” the report says. “He failed to satisfy us that his own donations had, in fact, come from sources within the UK.”

The committee heard evidence from 61 witnesses and received more than 150 written submissions. It held 20 oral evidence sessions, including one in Washington — the first time a select committee has held a live broadcast session in another country. A second report is expected to be published in the fall.

Collins said that during the 18-month probe, “what blew the doors off was when Wylie came forward.” That was the moment that “started to show the interconnectedness” of various digital advertising companies, such as Cambridge Analytica, SCL and AggregateIQ.

When asked if he thought micro-targeting by data analysis firms on sites such as Facebook actually influenced behavior, Collins said: “You wouldn’t spend millions of pounds doing it if you didn’t think it worked.”

Elizabeth Dwoskin in San Francisco contributed to this report.