The move is one of the first by Mr. Musk, a self-described free-speech absolutist, to tighten Twitter Inc.’s free-speech policies. He said Sunday that impersonating accounts will be permanently suspended unless they are specified as parody.
“No exceptions,” Mr. Musk wrote in a tweet.
Twitter’s rules currently say that people running impersonating accounts could be asked to edit their content otherwise they may be suspended.
Mr. Musk has brought dizzying changes to Twitter since he completed his $44 billion takeover of the platform late last month. He ousted the board, fired swaths of the workforce, including executives, and expanded the company’s subscription offerings.
His changes have brought confusion. The company said it started rolling out its updated subscription service on Saturday but it failed to materialize for most users.
Comedians may be confused by his policy change around impersonating accounts. Mr. Musk had tweeted on the day he completed his takeover: “Comedy is now legal on Twitter.”
When the comedians Ms. Griffin and Sarah Silverman, along with actor Rich Sommer, appeared to test that statement in recent days, they received different punishments. They had each temporarily changed their profile names, but not their handles, to “Elon Musk” and sent tweets pretending to be from him.
“I am a freedom of speech absolutist and I eat doody for breakfast every day,” Ms. Silverman wrote in a tweet on Saturday. She appeared to be referencing Mr. Musk’s free-speech philosophy.
Ms. Silverman’s account was temporarily locked but active on the platform as of Monday morning. The accounts of Ms. Griffin and Mr. Sommer were still suspended.
Mr. Sommer, who starred in “Mad Men,” said in a statement Monday, “I’m not mad at them for suspending me. I broke the rules.”
Representatives for Mr. Musk, Ms. Silverman, Ms. Griffin and Twitter didn’t immediately return requests for comment Monday.
The actress Valerie Bertinelli also posted tweets under Mr. Musk’s name over the weekend. She has since removed his name from her profile and her account wasn’t banned as of Monday morning. A representative for her declined to comment Monday.
Mr. Musk said on Twitter Sunday that he hadn’t banned an account that tracks his private jet because he was committed to free speech.
Jessie Hill, a law professor at Case Western Reserve University, said Monday that by banning accounts that make fun of him, Mr. Musk could have a chilling effect on speech on Twitter. That could mean people don’t tweet negative things about Mr. Musk because they’re afraid of being banned.
“It could sort of encourage people to self-censor,” said Ms. Hill, who has studied First Amendment and constitutional law.
Mr. Musk as a private citizen has a First Amendment right to censor speakers on his platform, she said. Still, she said the move wasn’t good for democracy because Twitter is a space where a lot of the country’s discourse happens.
Other social-media platforms, including Facebook and LinkedIn, don’t allow accounts that impersonate other people. Parody accounts are allowed on Facebook.
Margaret O’Mara, an American history professor at the University of Washington, said private companies are allowed to choose what type of discourse they allow on their platforms. That means Mr. Musk has to decide how he wants to moderate content on Twitter.
“In so many dimensions this is uncharted territory,” Ms. O’Mara, who has studied the technology industry, said regarding Mr. Musk’s views on content moderation and his management style on the subject.
Mr. Musk explained his policy change in additional tweets Sunday, saying users would no longer be warned before Twitter suspends their accounts.
“This will be clearly identified as a condition for signing up to Twitter Blue,” he wrote, referencing the company’s existing subscription service which he expanded to charge users $7.99 a month for verified accounts.
Mr. Musk said users who change their profile names would temporarily lose their verifications.
After Twitter suspended Ms. Griffin, her mother’s Twitter account began posting. Her mother died in 2020.
“#FreeKathy,” Maggie Griffin’s account wrote Sunday.
Mr. Musk wrote later Sunday, “if she really wants her account back, she can have it.”
“For $8,” he added, referencing the Twitter Blue subscription service.
Mr. Musk has taken aim at misinformation by criticizing accounts that impersonate him. He said Sunday that he wants Twitter to become the world’s most accurate source of information.
“Accurate to who?” Jack Dorsey, Twitter’s co-founder and former chief executive, replied Sunday.
Mr. Musk himself has been accused of spreading misinformation on the platform since he took it over. After House Speaker Nancy Pelosi’s husband was attacked in their home last month, Mr. Musk posted a link to an article with false information about the assault. He said it was possible there was more to the story than met the eye.
He later deleted the tweet.
