Perjury is a wilful and knowing telling of an untruth or a lie about a material fact under oath .
A material fact is a fact which could convince the jury to find in a civil case liability, for instance, rather than no liability, or in a criminal case reach a verdict of guilty rather than one of not guilty. Not stopping for a red light could be a material fact in either a civil or criminal case. Being a bottle blonde is unlikely to be a material fact in any case, civil or criminal. If someone filed false reports with the police, that would be considered false swearing , usually a lesser offense than perjury. If someone simply lied to someone else, that's not a crime . . .