Former President Donald Trump stormed out of his New York civil defamation trial on Friday — and attorney Areva Martin told CNN's Brianna Keilar that act likely shredded his credibility to the jury.

Writer E. Jean Carroll brought the suit over former President Donald Trump's repeated claims that she is lying about a sexual assault he's been found liable of committing against her. A previous jury last year hit him with $5 million in damages for sexually abusing and defaming her, and the current case is to assess additional damages for separate defamatory comments he made.

"Areva, this walk of Trump's out of court in the middle of E. Jean Carroll's lawyer's closing argument," said Keilar. "Could that cost the former president?"

"I hope it does, Brianna," said Martin, adding that Trump's walkout was "the most disrespectful display of petulance that we've ever seen."

This behavior, she continued, "goes right to the heart of the plaintiffs' closing argument, which is that Donald Trump thinks he's above the law. He doesn't have to play by the same rules that you or I or anyone else in a trial or in a courtroom has to play by. Throughout this trial, he has exhibited behavior, trust me, that if anyone else other than Donald Trump exhibited, this trial probably would have been over.

"The judge may have held him in contempt. He would have faced severe consequences."

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Among the behavior no other defendant would have gotten away with, she said, was when Trump muttered statements under his breath in front of the jury.

"Not only did he walk out, Brianna, we should note that one of his attorneys got up and walked out after he did. Again, that attorney would have been disciplined by the judge for engaging in that kind of conduct," said Martin. "So, I hope the message that E. Jean Carroll's lawyers sent about Donald Trump, sending this message that he's not above the law — I hope that resonates with these jurors."

Watch the video below or at the link here.

Areva Martin says Trump's "disrespectful display of petulance" will hurt him with the jurywww.youtube.com