* The most common issues that arise on exams regarding the requirements of an “actus reus” and a “mens rea” are the following:
Concurrence of mens reus and actus reus
* Concurrence between mens rea and actus reus is sometimes tested. When it is, the situation often involves a crime defined in terms of result (e.g., murder), and the hook is that what’s required is concurrence between mental state and act, not between mental state and result. So beware of cases where D changes his mind but can’t avoid the bad result — lack of concurrence won’t save D.
Example: D puts a bomb in V’s car, set to explode when the car is started. D has a change of heart, is afraid to disarm the bomb himself, and puts a sign on the windshield of the car saying “Do not start car — call the bomb squad.” The sign blows away, so V doesn’t see it. She starts the car and is blown away.
D is not saved from being guilty of murder because of any lack of concurrence. The required concurrence was between mens rea and actus reus (D’s voluntary act). D’s culpable mental state (intent to kill) coincided with his act (placing the bomb), so the requirement of concurrence was satisfied. The fact that D’s intent to kill did not coincide with the bad result (death) is irrelevant for the concurrence requirement.
Duty to act
* Duty-to-act is tested with some frequency on exams, because it calls for the close analysis of a fact pattern. Look for a party who fails to help another party in distress. Remember that a party is criminally liable for an omission only if there exists a duty for her to act.
+ Trap: Profs will try to distract you by presenting a very callous witness to an accident — one who fails to render aid. Don’t be swayed by unsympathetic feelings toward the bystander. Instead, concentrate on whether she had a duty to act. The ordinary bystander, who has no previous involvement with the peril, has no duty to act.
Example: A lifeguard at a public swimming pool leaves work early with the permission of her employer. While the pool is unattended a child falls in, striking her head against the edge of the pool. A bystander, B, witnesses the child’s fall, but fails to act, despite her knowledge that there is no lifeguard on duty and the fact that she is a strong swimmer. B had no duty to act and cannot be found guilty of any common-law crime.