WASHINGTON (WASHINGTON POST) - There is no dispute that the Facebook video of House Speaker Nancy Pelosi, a Democrat from California, viewed by millions is a fake, deliberately altered to make her appear drunk.

YouTube acted fast and removed duplicates. Other social media outlets have not made the same call.

Facebook acknowledged the video is "false" - but said the videos would remain on the platform.

Amid fierce calls across the public and government for Facebook to remove the video - which has been viewed 2.6 million times - and others like it, a Facebook official took to CNN on Friday (May 24) to defend its decision.

Ms Monika Bickert, a company vice president for product policy and counter-terrorism, said the video was reviewed by fact-checking organisations, and after it was deemed the video as a hoax, the company "dramatically" reduced its distribution.

But Facebook did not remove the video, Ms Bickert said.

"We think it's important for people to make their own informed choice for what to believe. Our job is to make sure we are getting them accurate information," she said.

A question has vexed lawmakers and Silicon Valley for years, particularly after massive disinformation campaigns were harnessed in the 2016 election: Should we consider platforms like Facebook "news publishers," and should they handle information like one?

Host Anderson Cooper believes the answer is yes, and pressed Ms Bickert on her company's responsibilities.

"You're making money by being in the news business," he said. "If you can't do it well, shouldn't you just get out of the news business?"

Ms Bickert rejected the premise in a tense back and forth. "We aren't in the news business. We're in the social media business," she said, adding the company removes content deemed a threat to public safety, or from fake accounts.

Mr Cooper shot back: "The reason you're sharing news is because you make money from it . . . but if you're in the news business, which you are, then you have to do it right. And this is false information you are spreading."

Ms Bickert said earlier in the segment that the original video is now tagged with fact-checker icons underneath the post.

But even internet novices have internalised small icons under posts as either related videos or advertisements and easily gloss over them, potentially missing Facebook's main effort to alert users over the disinformation.

"Why is she not arrested for being drunk while conducting federal business as a federal employee!" one Facebook user wrote in the video comment section on Saturday morning, hours after Ms Bickert said "anybody" who viewed the video was alerted about it. An expanded link for the video shows no fact-checker warnings.

The video was shared nearly 47,000 times from the original source, a conservative page called Politics WatchDog.

Twitter earlier declined to comment about company efforts around the video, taken on Wednesday at a Center for American Progress event, and several versions of the video remained on the platform Friday.

Lawmakers are focusing their criticism at Facebook, demanding the company take immediate action.

Representative David N Cicilline, a Democrat from Rhode Island, demanded Facebook "fix this now!"

Senator Brian Schatz, a Democrat from Hawaii, tweeted: "Facebook is very responsive to my office when I want to talk about federal legislation and suddenly get marbles in their mouths when we ask them about dealing with a fake video. It's not that they cannot solve this; it's that they refuse to do what is necessary."

Analyses of the distorted video by Washington Post journalists and outside researchers indicate that the video has been slowed to about 75 per cent of its original speed.

To possibly correct for how that speed change would deepen her tone, the video also appears to have been altered to modify her pitch, to more closely resemble the sound of her natural speech.

Analysts have warned about "deepfake" videos that use sophisticated editing and artificial intelligence software to create the appearance of someone recorded, which have been used to embarrass and harass targeted women.

But the Pelosi video is a clear example of even low-tech, relatively simple editing can dupe viewers and trigger widespread disinformation.

President Donald Trump's personal attorney Rudy Giuliani received the video in a text and shared it on Twitter before Facebook's response was issued, then later deleted it.