Definition - What does Perjury mean?
Perjury is the act of lying while under oath. Perjury is a criminal offense in all 50 states at both the state and federal levels. In most jurisdictions, there are two things that must be proved in order for a person to be charged with perjury. First, the person must have sworn or made a legal promise to tell the truth. Secondly, it must be shown that the individual purposely lied after having sworn to tell the truth.
Justipedia explains Perjury
It is a common misconception that any form of lying can warrant severe perjury charges. However, this is not always the case. Oftentimes, a minor (or irrelevant) lie is considered to be a misdemeanor while a material (or important) lie can be classified as a felony. Perjury is often considered to be a lie that affects the legal outcome of the situation. For example, if a person lied about having a goatee the previous summer, this would not necessarily be considered perjury. However, if the court is attempting to determine the identity of a robber and it is known that the robber had a goatee at the time of the robbery, then it would undoubtedly be classified as perjury if the individual stated that he did not have a goatee at that time if, in fact, he did.