President Donald Trump has accused Google of rigging the search results for the phrase “Trump news”.
In a tweet, he accused the technology giant of prioritising negative news stories from what he described as the “national left-wing media”.
He said most of the stories that appeared on the results page were negative and that conservative reporting was being “suppressed”.
Google denied using political viewpoints to shape its search results.
Mercedes Bunz, a senior lecturer in digital technology at King’s College London, told BBC News it was highly unlikely that Google was deliberately ranking news according to political bias.
“Google’s news algorithm is optimised for actuality and proximity of an event but it is generally not optimised to look for political orientation,” she said.
“However, it has a tendency to rank web pages higher that a lot of people link to.
“For news, this does not seem to have changed with Google’s last update of its search algorithm, which was rolled out on 1 August.”
Google states on its support page that there are “over 200 factors” that feed into the ranking of a web page on its search engine.
In his tweets, President Trump claimed that 96% of the news articles presented by Google in response to the phrase “Trump news” were from left-wing news outlets.
He did not name the source of this figure – but The Verge website reports it appears to have come from analysis by Paula Bolyard at the conservative news site PJ Media.
Ms Bolyard reported the 96% figure and said CNN had the greatest number of featured links, which President Trump mentioned as well.
“I performed the search multiple times using different computers – registered to different users – and Google returned similar results,” she wrote.
“While not scientific, the results suggest a pattern of bias against right-leaning content.”
Donald Trump’s tweets were posted the morning after a segment about Ms Bolyard’s report aired on Fox News, said Matthew Gertz from the American media watchdog Media Matters.
Google said its goal was to find the most relevant links to user queries, as quickly as possible.
“Search is not used to set a political agenda and we don’t bias our results toward any political ideology,” said a spokesperson.
“Every year, we issue hundreds of improvements to our algorithms to ensure they surface high-quality content in response to users’ queries.
“We continually work to improve Google Search and we never rank search results to manipulate political sentiment.”
When asked whether the White House was considering regulating Google, Trump’s economics advisor Larry Kudlow told journalists “we’re taking a look at it”, reported the Washington Post (paywall).