Common law defined criminal conduct by first looking at the mens rea or the offender’s “guilty mind.” Second, the common law looked at the actus reus or the offender’s “guilty act.” Finally, the common law weighed in the attendant circumstances. An important skill for a law school student is to be able to locate the mens rea, actus reus, and attendant circumstances in a definition of a crime.
For example, common law battery was defined as:
“The offense of battery occurs when a person actually and intentionally touches or strikes another against his or her will.”
- To determine the mens rea look for what describes the offender’s state of mind. Here, it is “intentionally.”
- To determine the actus reus look for what describes the offender’s action(s) that makes him guilty. Here, it is “actually…touchers or strikes another.”
- To determine the attendant circumstances look for the factors stem from the point of view of someone other than the defendant and that aggravate or mitigate the amount of culpability. Here, it is “against his or her will.”
Here is the common law definition of battery with the mens rea, actus reus, and attendant circumstances highlighted:
“The offense of battery occurs when a person actually and intentionally touches or strikes another against his or her will.”
A quick note on attendant circumstances: When determining what are attendant circumstances, it does not matter if the actor knows or intends to touch against the victim’s will. The actor’s guilty mind is not a factor in determining the attendant circumstances. In fact, attendant circumstances is actually from the point of view of someone other than the defendant (typically the victim). Also, it may be helpful if you think of attendant circumstances as those factors that would be helpful in determining a sentence, factors than can aggravate or mitigate the crime such as the amount of culpability.
Law school students should also know that under common law, the mens rea only modified the actus, not the attendant circumstances. Under our modern view, the mens rea modifies everything in the definition.