In opening arguments, Shane Vogt, a lawyer for the former wrestler, said that Gawker and its editors had deliberately shown his client “naked and exposed to the world” for six months on the site, generating millions of views, despite repeated requests by Mr. Bollea to take the video down. Mr. Vogt said that the situation had caused extreme “emotional distress and harm” to his client, a central point in Mr. Bollea’s pursuit of damages in the case.

“If they had taken down the video,” Mr. Vogt said, “we wouldn’t be here today.”

The 30-minute video, apparently filmed in 2007 and later provided to Gawker, garnered five million page views when it was posted in an abridged version on the site in 2012 and 2.5 million views on other sites that posted it subsequently, Mr. Bollea’s lawyer said. In posting the video, he continued, Gawker allowed the public to watch Mr. Bollea having sex in a private bedroom without his knowledge or consent.

Gawker’s founder, Nick Denton, and its former editor, A. J. Daulerio, who is also named in the suit, “knowingly and maliciously” published what Mr. Vogt called the pornographic images for the sole purpose of financial gain. The posts violated Florida law, he said — specifically a measure that prohibits the publication of private communications without permission — as well as basic human decency.

“They’re going to try to tell you that what they were doing was news,” Mr. Vogt said, in an effort to dismiss a crucial element of the defense’s case: that the activities of well-known people are a subject of public concern. “They crossed the line when they posted this video. It was not newsworthy.”

In his opening statement, a lawyer for the Gawker team, Michael Berry, told the jury that videotapes featuring celebrities like Paris Hilton and Kim Kardashian having sex have become a “cultural phenomenon,” and that such images are of interest to the public and therefore protected by the First Amendment.