Mens Rea

The materials in this section introduce you to the concept of mens rea:  the state of mind specified by statute that must be proven for a conviction. Like actus reus, mens rea weaves together ideas about the offender's blameworthiness, the seriousness of the crime, and the punishment that should be imposed. 

Historically, some crimes were considered to be "general intent" crimes and others were "specific intent" crimes. (See Note 4.21 in this unit.) The MPC, whose definition is now used in many states, categorizes intent into four tiers of culpability: purposely (acting with a conscious objective to produce the offense specified in the statute); knowingly (acting while being practically certain of the offending result); recklessly (acting with a conscious disregard for the risk of causing the offending result); and negligently (causing the offending result when the actor should have been aware of the risk). 

Beyond these forms of guilt, you will find what are known as strict liability offenses: crimes for which the defendant's state of mind is irrelevant. These typically involve acts/harms determined to be particularly injurious to public health and must be deterred/punished regardless of intent. To be convicted under a strict liability statute, the defendant must only have committed a voluntary act (actus reus) that caused the harmful result (causation) the statute was designed to prevent. Some examples of strict liability offenses are traffic violations, statutory rape, and felony murder.  

As you read these cases, consider what reasoning courts use to justify their decisions and what these reasons reveal about the evolving concept of blameworthiness. Always pay close attention to how the "guilty" state of mind is framed by the relevant statute(s) and the relationships between various mens rea and the severity of punishment. 

While many statutes will seem loosely based on the four-tiered MPC framework, you should not assume they are identical. It is important to remember that the enacted legislation, and not the MPC, is what controls within any jurisdiction. In other words, even if a statute uses the mens rea term "intentional" in a manner akin to the MPC's definition of "purposeful," you may not substitute one term for another. As you work through these cases, train yourself to focus squarely on the actual language of a given statute and how a lawyer advocating for either side might interpret it.