MBE Criminal Law - Defenses

Capacity (insanity, intoxication, etc)

Justification (self-defense, etc)

M’Naghten;

Irresistible Impulse;

Durham/New Hampshire test; and

Model Penal Code standard

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

Looks at whether D is incapable of controlling his behavior.

⭐️ Many states use both M’Naghten & the Irresistible Impulse test.

D will be acquitted if his actions were the product of a mental disease or defect (“but for”)

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.

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

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

They have completely withdrawn, communicated that to V, and V reattacks/continues attacking; or

They used nondeadly force and V responded with deadly force

No, V may not act in a manner that a reasonable person would find inappropriate

A person in his or her own home has no duty to retreat from the use of deadly force for protection

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

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

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)

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

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

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)

Yes, as either temporary insanity or negation of requisite intent (either general or specific)

Taking a substance:

Under duress; or

Without knowledge of its effects (lack of knowledge must be reasonable)

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

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

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)

Only if the mistake prevented D from having the requisite mens rea for the crime

⚠️ Note: Mistake can be either reasonable or unreasonable