What are the two general types of defenses for specific intent crimes?
- Capacity (insanity, intoxication, etc)
- Justification (self-defense, etc)
What are the tests for insanity?
- M’Naghten;
- Irresistible Impulse;
- Durham/New Hampshire test; and
- Model Penal Code standard
Elements of M’Naghten test
- D suffered from a mental disease or defect in reasoning; and
- D was unable to understand the “nature and quality” of his act OR that what he was doing was wrong
Define
Irresistible Impulse test
Looks at whether D is incapable of controlling his behavior.
⭐️ Many states use both M’Naghten & the Irresistible Impulse test.
Define
Durham/New Hampshire test
D will be acquitted if his actions were the product of a mental disease or defect (“but for”)
What is the MPC test for insanity?
As a result of mental disease or defect, D lacks substantial capacity to either:
- Appreciate the criminality of his conduct; or
- Conform his conduct to the requirements of the law
⭐️ Note: Success under either the M’Naghten test or Irresistible Impulse test will satisfy the MPC standard.
What are justification/excuse defenses?
Argues that D’s conduct was justified under the particular facts of the case. Includes:
- Self-defense;
- Defense of others;
- Defense of property;
- Necessity;
- Duress;
- Crime prevention, arrest and to prevent escape; and
- Entrapment
Elements of self-defense
- D honestly and reasonably believed;
- That he was subject to an imminent unlawful use or threat of force; and
- D used proportional force to defend himself
When can first aggressors claim self-defense?
- They have completely withdrawn, communicated that to V, and V reattacks/continues attacking; or
- They used nondeadly force and V responded with deadly force
Can V act negligently when using self-defense?
No, V may not act in a manner that a reasonable person would find inappropriate
Define
castle doctrine
A person in his or her own home has no duty to retreat from the use of deadly force for protection
When can D invoke a defense of others claim?
If D:
- Reasonably believed V was in imminent danger of great bodily harm;
- Used force proportional to prevent the harm; and
- Reasonably believed V would have had a right of self-defense
When is the defense of property allowed?
Non-deadly force is justified if:
- D has a reasonable belief that the property is in imminent danger; and
- D did not use more force than what was necessary to prevent the interference
Can you use deadly force to protect property?
No, unless:
- Intruder has broken into dwelling (i.e. your occupied home);
- There is reasonable fear of an immiment felony being committed; and
- Force is necessary to prevent such intrusion
⚠️ Modern view: deadly force to protect one’s home is only allowed if D has a fear of an immiment violent felony being committed (e.g. homeowner sees intruder with a gun)
Elements to the defense of necessity
- There is an immediate threat of greater harm to persons or property unless D commits the act;
- No reasonable alternative to breaking the law; and
- D is not responsible for causing the intial harm
⚠️ Note: Economic necessity is not valid justification
Elements for duress defense
- Imminent threat by third party;
- Of serious great bodily harm or death;
- That reasonably causes D to become fearful;
⚠️ Note: Duress is not allowed as a defense for homicide
Is voluntary intoxication a defense?
No, unless used to show that D could not have formed or possessed the requisite intent for a crime (i.e. only for specific intent crimes)
Is involuntary intoxication a defense?
Yes, as either temporary insanity or negation of requisite intent (either general or specific)
What qualifies as involuntary intoxication?
Taking a substance:
- Under duress; or
- Without knowledge of its effects (lack of knowledge must be reasonable)
Is consent a valid defense?
Yes, only if:
- Consent is an element of the crime; or
- Consent is for non-serious bodily harm that occurs during a lawful athletic activity or competition
AND
- The consent was voluntarily given by a person with legal capacity to consent
Elements of entrapment defense
- Government designed the crime and encouraged its commission; and
- D was not predisposed to commit the crime prior to engagement with law enforcement
⚠️ Very limited defense that rarely works
Is mistake of law a valid defense?
Generally not. Only successful in extremely rare circumstances if:
- D reasonably relied on a statute that is invalid; or
- Crime requires knowledge of the law itself (ex. crime requires D to “willfully” violate it; often applies to complicated tax laws)
Is mistake of fact a valid defense?
Only if the mistake prevented D from having the requisite mens rea for the crime
⚠️ Note: Mistake can be either reasonable or unreasonable
