On August 17, 1998, the Grand Jury questioned President Bill Clinton regarding his relationship with White House intern Monica Lewinsky. They were trying to determine the exact nature of President Clinton's relationship with Ms. Lewinsky and if he had previously lied under oath when he testified that he had not had an affair with her. The President's defense during the questioning relied on elaborate definitions of certain words such as, "alone" "sexual relations" and "sex", but the most confusing semantic argument was regarding the word "is". When questioned, President Clinton said, "It depends upon what the meaning of the word "is" is". (The dictionary defines "is" as; 3rd person singular of the present tense of "be").
President Clinton was finally forced into admitting the affair with the introduction into evidence of the now infamous "blue dress".
And here's President Clinton in action.