27Criminal Law

Defenses: Excuse

Excuse defenses acknowledge wrongful conduct but eliminate punishment because the actor's mental state, circumstances, or capacity negates moral culpability. This week covers insanity (M'Naghten, irresistible impulse, MPC/ALI), intoxication (voluntary vs. involuntary), duress, infancy, entrapment, and mistake of law/fact.

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Learning Objectives

Apply the four insanity tests: M'Naghten (cognitive), irresistible impulse (volitional), MPC/ALI (substantial capacity), and Durham (product)
Distinguish voluntary intoxication (specific intent defense only) from involuntary intoxication (treated like insanity)
Analyze duress: reasonable belief in imminent death/serious bodily harm to self or family from another person; not available for homicide
Apply the infancy defense at common law (under 7 = no capacity; 7-14 = rebuttable presumption; 14+ = adult)
Distinguish subjective entrapment (predisposition test) from objective entrapment (government conduct test)

Key Rules

M'Naghten test (majority): At the time of the act, defendant suffered a mental disease or defect such that they (1) did not know the nature and quality of the act, OR (2) did not know the act was wrong.
Voluntary intoxication: A defense only to SPECIFIC INTENT crimes (not general intent, malice, or strict liability). Defendant must be so intoxicated as to be incapable of forming the required specific intent.
Involuntary intoxication: Treated like insanity — full defense to any crime if it rendered defendant unable to distinguish right from wrong or understand the nature of the act.
Duress: (1) Threat of imminent death or serious bodily harm, (2) to defendant or close family member, (3) from another person (not circumstances), (4) reasonable belief the threat is genuine. NEVER a defense to intentional homicide.
Entrapment (subjective/majority): Government induced the defendant to commit a crime they were not predisposed to commit. If defendant was predisposed, no entrapment regardless of government conduct.

Defenses: Excuse

Excuse vs. Justification (Review)

- Justification: The act was RIGHT (self-defense, necessity) - Excuse: The act was WRONG but the actor is NOT PUNISHABLE (insanity, duress)

Insanity

The Four Tests

| Test | Focus | Standard | |------|-------|----------| | M'Naghten (majority) | Cognitive | Did not know nature of act OR that it was wrong | | Irresistible Impulse | Volitional | Could not control conduct despite knowing it was wrong | | MPC/ALI | Both | Lacked substantial capacity to appreciate criminality OR conform conduct | | Durham (minority) | Causation | Act was product of mental disease |

Intoxication

| Type | Defense To | Not a Defense To | |------|-----------|------------------| | Voluntary | Specific intent crimes only | General intent, malice, strict liability | | Involuntary | Any crime (treated like insanity) | — |

Duress

Elements: (1) Threat of imminent death/SBH, (2) to D or close family, (3) from another person, (4) reasonable belief, (5) no reasonable escape.

NEVER a defense to intentional homicide — the law does not permit taking an innocent life to save your own.

Baby Bar Connection

Excuse defenses are tested when fact patterns involve defendants with mental illness, intoxication, or external pressure. The voluntary intoxication rule (specific intent only) is a particularly common exam trap.

Cases to Know

M'Naghten's Case (1843) — foundational insanity test: did not know nature/quality of act or that it was wrong
People v. Hood (1969) — voluntary intoxication not a defense to assault (general intent) in California

California Codes — Official Authority

The statutes SofAI ties to this topic. Use them as your IRAC rule block, then verify the current text on the official leginfo link.

Cal. Penal Code §26 — Persons capable of committing crime (defenses)leginfo
Certain people are not capable of committing crimes, including some minors and people acting under a mistake of fact or without criminal intent.

Explore all California Codes

Baby Bar Relevance

Excuse defenses — particularly voluntary intoxication (specific intent only) and insanity — are commonly tested. The key is correctly classifying the charged crime as specific or general intent BEFORE applying the intoxication defense.

Week 26 Back to Dashboard Week 28

Defenses: Excuse

Learning Objectives

Apply the four insanity tests: M'Naghten (cognitive), irresistible impulse (volitional), MPC/ALI (substantial capacity), and Durham (product)

Distinguish voluntary intoxication (specific intent defense only) from involuntary intoxication (treated like insanity)

Analyze duress: reasonable belief in imminent death/serious bodily harm to self or family from another person; not available for homicide

Apply the infancy defense at common law (under 7 = no capacity; 7-14 = rebuttable presumption; 14+ = adult)

Distinguish subjective entrapment (predisposition test) from objective entrapment (government conduct test)

Key Rules

M'Naghten test (majority): At the time of the act, defendant suffered a mental disease or defect such that they (1) did not know the nature and quality of the act, OR (2) did not know the act was wrong.

Voluntary intoxication: A defense only to SPECIFIC INTENT crimes (not general intent, malice, or strict liability). Defendant must be so intoxicated as to be incapable of forming the required specific intent.

Involuntary intoxication: Treated like insanity — full defense to any crime if it rendered defendant unable to distinguish right from wrong or understand the nature of the act.

Duress: (1) Threat of imminent death or serious bodily harm, (2) to defendant or close family member, (3) from another person (not circumstances), (4) reasonable belief the threat is genuine. NEVER a defense to intentional homicide.

Entrapment (subjective/majority): Government induced the defendant to commit a crime they were not predisposed to commit. If defendant was predisposed, no entrapment regardless of government conduct.

Insanity

The Four Tests

California Codes — Official Authority

The statutes SofAI ties to this topic. Use them as your IRAC rule block, then verify the current text on the official leginfo link.

Cal. Penal Code §26 — Persons capable of committing crime (defenses)leginfo

Certain people are not capable of committing crimes, including some minors and people acting under a mistake of fact or without criminal intent.

Explore all California Codes