PHOENIX - Comedian Kathy Griffin has apologized for a photo shoot that depicted her holding what appeared to be a fake severed head of Donald Trump.

In a Twitter post, Griffin admitted she "crossed the line". But did her photo shoot cross a legal line?

First Amendment attorney Dan Barr said Griffin's case would fall under a U.S. Supreme Court case called Brandenburg v. Ohio which involved statements made at a Ku Klux Klan rally. The Supreme Court ruled statements advocating violence are protected under the First Amendment as long as the violence are not "imminent, likely and intended."

"Here, as horrifically in bad taste as Kathy Griffin's video may be," Barr said, "the violence is not intended. The violence is not imminent."

That's not to say the Secret Service can't -- or won't -- investigate anything it perceives as a threat to the president. But Barr said investigating is not the same as arresting.

CNN has since cut ties with Griffin, who has hosted the network's New Year's Eve show for years, despite her apology.

While Griffin's actions may be protected under the First Amendment, the consequences to her career are not.