WASHINGTON — Former US President Donald Trump on Wednesday (July 7) filed lawsuits against Twitter, Facebook, and Alphabet's Google, as well as their chief executives, alleging they unlawfully silence conservative viewpoints.

The lawsuits, filed in US District Court in Miami, allege the California-based social media platforms violated the right to freedom of speech guaranteed by the First Amendment of the US Constitution.

Mr Trump is seeking class action status for the lawsuits, meaning he would represent the interests of other users of Twitter, Facebook, and Google's YouTube who allege they have been unfairly silenced.

He filed three lawsuits making similar allegations — one against Facebook and its Chief Executive Officer (CEO) Mark Zuckerberg, one against Twitter and its CEO Jack Dorsey, and one against Google and its CEO Sundar Pichai.

"We will achieve a historic victory for American freedom and at the same time, freedom of speech," Mr Trump said at a news conference at his golf course in Bedminster, New Jersey.

A Twitter representative declined to comment. Representatives of Facebook and Google did not immediately respond to requests for comment.

Mr Trump lost his social media megaphone this year after the companies said he violated their policies against glorifying violence.

Hundreds of his supporters launched a deadly assault on the US Capitol on Jan 6 after a Trump speech repeating his false claims that his election defeat was the result of widespread fraud, an assertion rejected by multiple courts, state election officials and members of his own administration.

The lawsuits ask a judge to invalidate Section 230 of the Communications Decency Act, a law that has been called the backbone of the internet because it provides websites with protections from liability over content posted by users.

Mr Trump and others who have attacked Section 230 say it has given big internet companies too much legal protection and allowed them to escape responsibility for their actions.

"This complaint is hard to even make sense of," said Dr Paul Gowder, a professor of law at Northwestern University.

Mr Trump sought to portray the social media companies as subject to the same First Amendment requirements as government entities when it comes to censorship, but Dr Gowder said nothing in the lawsuits "even comes close to turning social media companies into government actors."

A federal judge in Florida last week blocked a recently enacted state law that was meant to authorise the state to penalise social media companies when they ban political candidates, with the judge saying the law likely violated free speech rights.

The lawsuit said the bill signed by Florida's Republican Governor Ron DeSantis in May was unconstitutional. It would have made Florida the first state to regulate how social media companies moderate online speech. REUTERS