The terms "false witness" and "corrupt witness" refer to a person who says untrue things about a person or an event, usually in a formal setting such as a court.
* To "bear false witness" or "give a false testimony" could be translated as "testify falsely" or "give a false report about someone" or "speak falsely against someone" or "lie."
* When "false witness" refers to a person, it could be translated as "person who lies" or "one who testifies falsely" or "someone who says things that are not true."