That is called perjury and can lead to fine and/or imprisonment. It might also lead to a guilty verdict, if the jury thinks that the defendant is a liar and is probably guilty of the crime.
Added: It would be up to the prosecutor to impeach the defendant and refute his version of affairs by the production of evidence and testimony to the contrary.
Under what circumstances and what is your intent?
Clinton had had an improper relationship with a White House intern. And he allegedly had lied about it under oath.
He was charged with nothing at all. The charges were ultimately dropped
Yes. Perjury occurs anytime you're under oath and lie.
He did go to a congress trial but he won.
If you lied under oath, then yes. You could be charged with perjury.
She committed perjury when she lied under oath during the trial.
All persons who give testimony in court are sworn under oath to tell the truth, even when an oath is not actually administered it is presumed by law that the person has agreed to such. All persons who deliberately lie or withold known information while under oath are subject to perjury charges.
vowed: verb: synonyms: promised, pledged, oath vowed: verb: antonyms: lied, fibbed, perjured
Bill Clinton did commit perjury. He was under oath when he said he had never had sexual relations with Monica Lewinsky. Later, he did admit to the affair. Although his affair is really of no concern to the American people, he still lied under oath. This was and still is an act of perjury.
He was cheating on his wife with a white house lady. He lied under oath and no one liked him anymore.
No bearing whatsoever. He can question and cross-examine witnesses without taking the stand and testifying under oath in his own trial.