During closing arguments, can a lawyer turn around in front of the jury, and call the opposing lawyer, a liar? A Lawyer cannot Call the Opposing Lawyer a Liar The plaintiff’s lawyer says its black, the defense will say white, one side says yes and the opposing side says no. For, everything claimed by the plaintiff, the defense would say just the opposite. Is the defense lying or being untruthful? Is the defense lawyer shading the truth? When the plaintiff’s lawyer obtains the opportunity to address the jury with his closing remarks at the end of the trial, can he tell the jurors that the