The former head of news at the News of the World told the Leveson media inquiry that a "culture of bullying" existed at the paper that "emanated from the editor".
Ian Edmondson was the news editor at the NotW between November 2005 and 2011.
He was arrested with Neville Thurlbeck, the paper's former chief reporter, on 5 April 2011 by officers investigating phone hacking at the newspaper, and is set to answer bail in March.
He said: "It's a case of you will do as you are told and you live in that environment."
"It's not a democracy at a newspaper," he added. "It's autocratic."
Edmondson also said he didn't "recall" writing emails appearing to threaten women to tell their side of a story involving Max Mosley.
The former boss of Formula 1 received £60,000 of damages after the NotW published a front page story about his encounter with five paid sex workers in London.
Mosley has since campaigned for the subject of newspaper stories to be given notice before publication. He gave evidence to the inquiry in November 2011.
The emails in question offered the women a chance to tell their story to the NotW anonymously, but also said the paper would publish their names and photographs without pixelation if they did not cooperate.
Thurlbeck told the inquiry in December that while he had sent the emails Edmondson had drafted them.
But Edmondson claimed in his evidence that while he had "no doubt" he had asked Thurlbeck to get in touch with the women, the emails were not "the language I would have used".
He insisted that it was "very, very unlikely" he would have written the emails, and said he interpreted the message behind them as a "threat".
Of the emails, Edmondson said: "I don't like its tone".
Leveson asked him: "As you read the emails now, what's your reaction to them?"
"I think they are a threat," Edmondson said.
Leveson replied: "I think we can agree about that."
Edmondson told the inquiry that Colin Myler had told him not to inform Kate McCann, mother of the missing girl Madeleine McCann, that the paper had her diary.
Kate McCann described reading extracts from her diary in the paper as being "mentally raped" in her evidence to the inquiry in November.
Lord Justice Leveson asked Mr Edmondson: "Did you lead Mr Myler to believe that you had made it clear to Mr Mitchell that you had the whole diary and were going to cause extracts from it to be published in the News of the World?"
The former news editor said he presented an "alternative" to Myler so the newspaper could work together with the McCanns to publish the diary, but the collaborative option had been rejected by the editor.
Edmondson also defended employing private investigator Derek Webb as a journalist, because he had "useful" skills which were used in the course of "journalistic tasks".
He admitted that he knew there was a ban in place on using private detectives, and discussed Webb joining the National Union of Journalists and changing his email address from "Silent Shadow" to "Derek Webb Media".
Other witnesses appearing at the Royal Courts of Justice in central London today include Heather Mills, the former wife of Sir Paul McCartney, PR guru Max Clifford, Darryn Lyons, who founded picture agency Big Pictures, and general secretary of the National Union of Journalists, Michelle Stanistreet.
Prime Minister David Cameron set up the Leveson Inquiry last July in response to revelations that the News of the World commissioned a private detective to hack murdered schoolgirl Milly Dowler's phone after she disappeared in 2002.
The first part of the inquiry, which is now coming to an end, is looking at the culture, practices and ethics of the Press in general and is due to produce a report by September.
The second part, examining the extent of unlawful activities by journalists, will not begin until detectives have completed their investigation into alleged phone-hacking and corrupt payments to police, and any prosecutions have been concluded.