In criminal law, mens rea (/ˈmɛnz ˈreɪə/; Law Latin for "guilty mind") is the mental element of a person's intention to commit a crime; or knowledge that one's action (or lack of action) would cause a crime to be committed. It is considered a necessary element of many crimes. The types of mental states that apply to crimes vary depending on whether a jurisdiction follows criminal law under the common law tradition or, within the United States, according to the Model Penal Code. In some jurisdictions, the terms mens rea and actus reus have been replaced by alternative terminology.