Commonly Confused Doctrines — Side by Side

COMMONLY CONFUSED DOCTRINES — SIDE BY SIDE

37 side-by-side tables for the doctrines students most often mix up. Learn the distinguishing line, not just the names.

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Criminal Law

Theft Crimes Compared

Aspect	Larceny	Embezzlement	False Pretenses	Larceny by Trick
What the defendant acquires	Possession of another's property	Already-entrusted property converted	Title to the property	Possession obtained through deception
How property comes to defendant	Wrongful taking & carrying away	Lawful entrustment, then conversion	Victim voluntarily transfers ownership	Victim hands over possession, fooled by a lie
What the deceit accomplishes	No deceit; trespassory taking	No deceit at taking; abuse of trust	Induces transfer of title	Induces transfer of possession only
When intent must exist	At the moment of taking	At the moment of conversion	When the misrepresentation is made	At the time possession is obtained
Classic fact pattern	Pickpocket grabs a wallet	Bank teller skims the till	Buyer pays with a worthless check for title	Borrows a car claiming a quick errand, keeps it

Robbery vs. Extortion vs. Burglary

Aspect	Robbery	Extortion (Blackmail)	Burglary (Common Law)
Core wrong	Larceny by force or fear	Obtaining property by threats	Unlawful entry to commit a crime inside
Victim's presence	Property taken from person or presence	Victim need not be present	Targets a structure, not a person directly
Timing of the threat	Threat of immediate harm now	Threat of future harm	No threat element required
Was property actually taken	Yes, completed taking required	Some jurisdictions complete on the threat alone	Not required; intent at entry suffices
Signature element	Force or intimidation at the scene	Coercive demand (e.g., expose a secret)	Breaking & entering a dwelling at night with felonious intent

Voluntary vs. Involuntary Manslaughter

Aspect	Voluntary Manslaughter	Involuntary Manslaughter
Mental state	Intent to kill present but mitigated	No intent to kill
Mitigating trigger	Adequate provocation; heat of passion	Criminal negligence or recklessness
Cooling-off period	No reasonable time to cool off	Not applicable
Alternate route	Imperfect self-defense (some states)	Death during an unlawful act (misdemeanor-manslaughter)
Relation to murder	Murder reduced by provocation	Killing that never rose to murder

Murder Degrees & Malice

Aspect	First-Degree Murder	Second-Degree Murder	Felony Murder
Mental state	Premeditated, deliberate intent to kill	Malice without premeditation	Malice implied from the felony
Planning required	Yes, prior reflection however brief	No advance planning needed	No intent to kill needed at all
Typical malice form	Express intent to kill	Intent to do serious bodily harm or depraved heart	Transferred from inherently dangerous felony
Required predicate	None beyond the killing	None beyond the killing	An enumerated or inherently dangerous felony
Example	Lies in wait for the victim	Reckless gunfire into a crowd	Clerk dies during an armed robbery

Specific vs. General vs. Strict-Liability Intent

Aspect	Specific Intent	General Intent	Strict Liability
What prosecution proves	Intent to achieve a particular result	Awareness of doing the prohibited act	Only that the act occurred
Mistake-of-fact defense	Any honest mistake may negate intent	Only a reasonable mistake	No mistake defense available
Voluntary intoxication	Can negate the specific intent	Generally not a defense	Irrelevant
Typical crimes	Larceny, burglary, conspiracy, attempt	Battery, rape, kidnapping	Statutory rape, selling adulterated goods

Inchoate Crimes: Attempt vs. Conspiracy vs. Solicitation

Aspect	Attempt	Conspiracy	Solicitation
Conduct required	Substantial step beyond mere preparation	Agreement (plus an overt act in most states)	Asking or encouraging another to commit a crime
Number of people	One actor	At least two minds (traditional view)	One actor making the request
Merger into completed crime	Merges; cannot punish both	Does not merge with the target crime	Merges into attempt or completed crime
Abandonment	Limited; some allow withdrawal	Withdrawal limited and individual	Renunciation defense in some states
Completion point	When the step is taken	When agreement (and overt act) occurs	When the encouragement is communicated

Insanity Tests Compared

Aspect	M'Naghten	Irresistible Impulse	MPC (Model Penal Code)	Durham
Focus	Cognitive: knowing right from wrong	Volitional: ability to control conduct	Both cognition and control	Product of mental disease
Defendant excused if	Couldn't understand nature or wrongfulness	Couldn't resist the impulse to act	Lacked substantial capacity to appreciate or conform	Act was a product of mental illness
Standard's breadth	Narrow, knowledge-based	Adds loss of control	Moderate; substantial (not total) incapacity	Broadest and most criticized
Modern status	Most common majority test	Often paired with M'Naghten	Adopted by many modern codes	Largely abandoned

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Contracts

Common Law vs. UCC Article 2

Aspect	Common Law (Services/Land)	UCC Article 2 (Goods)
Acceptance terms	Mirror image rule; must match exactly	Acceptance can add terms (2-207)
Contract modification	Requires new consideration	Good faith suffices; no new consideration
Irrevocable offers	Option requires consideration	Merchant's firm offer binding without consideration
Performance standard	Substantial performance excuses minor breach	Perfect tender; buyer may reject for any nonconformity
Implied warranties	Generally none	Merchantability and fitness implied
Missing terms	Often fatal if essential terms absent	Court fills gaps (price, place, time)

Battle of the Forms (UCC 2-207)

Aspect	Both Merchants	At Least One Non-Merchant
Additional terms in acceptance	Become part of the contract automatically	Treated as mere proposals
When additional terms drop out	If they materially alter the deal	Unless expressly assented to
Objection window	Excluded if objected to within reasonable time	Need affirmative agreement
Different (conflicting) terms	Often knocked out, gaps filled by Code	Same knockout reasoning typically applies
Effect on contract formation	Definite acceptance still forms a contract	Acceptance forms a contract on offeror's terms

Contract Damages Compared

Aspect	Expectation	Reliance	Restitution	Consequential
Goal	Put plaintiff in position if performed	Reimburse out-of-pocket losses	Prevent unjust enrichment	Compensate foreseeable special losses
Measured by	Benefit of the bargain	Costs incurred in reliance	Value conferred on defendant	Losses defendant had reason to foresee
When used	Default contract remedy	When expectation is speculative	When no enforceable contract exists	Add-on when Hadley foreseeability met
Limiting doctrine	Certainty and foreseeability	Cannot exceed expectation	Quantum meruit ceiling	Must be foreseeable at contracting

Third-Party Beneficiaries, Assignment & Delegation

Aspect	Intended Beneficiary	Assignment of Rights	Delegation of Duties
What is transferred	Benefit created at formation	A contractual right to receive performance	A contractual obligation to perform
Who may enforce	The third party, once rights vest	The assignee	The obligee enforces against either party
Consent needed	No; built into the original deal	Generally none unless materially burdensome	None unless duties are personal or special
Original party's liability	Promisee may still sue promisor	Assignor's role ends on valid assignment	Delegator remains liable as a surety

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Real Property

Possessory Estates Compared

Aspect	Fee Simple Determinable	Fee Simple Subject to Condition Subsequent	Fee Simple Subject to Executory Limitation
Durational language	“so long as,” “while,” “until”	“provided that,” “but if,” “on condition”	“but if X, then to a third party”
Future interest held	Possibility of reverter (grantor)	Right of entry / power of termination (grantor)	Executory interest (third party)
How it ends	Automatically on the stated event	Only if grantor affirmatively re-enters	Automatically shifts to the third party
Who takes after	Returns to the grantor	Grantor, after asserting the right	A named transferee, not the grantor

Remainders & Executory Interests

Aspect	Vested Remainder	Contingent Remainder	Executory Interest
Holder identified	Ascertained person	Unborn or unascertained, or condition unmet	Identified, but interest cuts short prior estate
Condition precedent	None remaining	Yes, must be satisfied first	Springs or shifts on a future event
Follows naturally?	Takes immediately when prior estate ends	Takes only if the contingency resolves	Divests another's estate
RAP exposure	Generally vested, often safe	Subject to the Rule	Subject to the Rule
Subtypes	Indefeasibly vested; subject to open; subject to divestment	Condition or unascertained taker	Springing (from grantor) or shifting (from grantee)

Non-Possessory Land Interests

Aspect	Easement	License	Profit	Real Covenant	Equitable Servitude
Nature of right	Right to use another's land	Permission to enter, revocable	Right to take resources from land	Promise to do or not do something	Promise enforced in equity
Revocable?	No, once validly created	Yes, freely revocable	No	No	No
Writing required	Yes (Statute of Frauds)	No	Yes	Yes	Yes (or common scheme)
Remedy for breach	Enforced as a property right	None; just permission	Property right enforcement	Money damages at law	Injunction in equity
Runs with the land if	Appurtenant and proper notice	Does not run	Like an easement	Privity plus notice plus touch & concern	Notice plus touch & concern (no privity needed)

Concurrent Ownership Forms

Aspect	Joint Tenancy	Tenancy in Common	Tenancy by the Entirety
Right of survivorship	Yes	No	Yes
Four unities required	Time, title, interest, possession	Only unity of possession	Four unities plus marriage
Unilateral transfer	Severs into a tenancy in common	Freely transferable	Neither spouse can convey alone
Creditor reach	Creditor may sever the joint tenancy	Reaches that owner's share	Generally protected from individual creditors
Default presumption	Disfavored; clear intent required	Modern default for co-owners	Available only to married couples

Recording Acts Compared

Aspect	Race	Notice	Race-Notice
Who prevails	First to record, period	Last bona fide purchaser without notice	BFP without notice who records first
Must subsequent buyer record?	Yes, recording is the whole contest	No, recording not required to win	Yes, must record before the prior grantee
Must subsequent buyer lack notice?	No, notice irrelevant	Yes, must lack notice when buying	Yes, must lack notice when buying
Statutory clue	“first recorded”	“in good faith” / “without notice”	“in good faith … first recorded”

Adverse Possession vs. Prescriptive Easement

Aspect	Adverse Possession	Prescriptive Easement
What is gained	Title to the land itself	A right to use the land
Exclusivity	Must be exclusive	Need not be exclusive
Possession vs. use	Actual possession required	Continuous use, not possession
Common elements	Open, notorious, hostile, continuous for the period	Open, notorious, hostile, continuous for the period
Outcome	Original owner is divested	Owner keeps title, burdened by the use

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Torts

Negligence Defenses Compared

Aspect	Contributory Negligence	Pure Comparative	Modified Comparative
Effect of plaintiff's fault	Total bar to recovery	Reduces recovery by fault percentage	Reduces, then bars past a threshold
Recovery if 90% at fault	None	Recovers 10%	Barred (over 50%)
Threshold cutoff	Any fault bars	No cutoff	Barred at 50% or 51%
Last clear chance	Plaintiff can rebut the bar	Doctrine absorbed into apportionment	Doctrine absorbed into apportionment
Modern prevalence	Minority of states	Several states	Majority approach

Intentional Torts to the Person

Aspect	Battery	Assault	False Imprisonment	IIED
Core act	Harmful or offensive contact	Apprehension of imminent contact	Confinement to a bounded area	Extreme and outrageous conduct
Contact needed?	Yes	No, apprehension suffices	No physical force needed	No
Plaintiff's awareness	Not required	Must be aware of the threat	Must know or be harmed by confinement	Must actually suffer severe distress
Mental state	Intent to contact	Intent to cause apprehension	Intent to confine	Intent or recklessness
Damages	Presumed; no harm needed	Presumed	Presumed	Severe emotional distress required

Strict Liability vs. Negligence vs. Products Liability

Aspect	Negligence	Strict Liability	Strict Products Liability
Fault required	Breach of a duty of care	No fault needed	No proof of carelessness needed
Typical triggers	Unreasonable conduct	Abnormally dangerous activities; wild animals	Defective product reaching the consumer
Defendant class	Anyone owing a duty	The actor undertaking the risk	Commercial seller in the chain
Plaintiff must show	Duty, breach, causation, damages	Activity, causation, harm	Defect existed when it left the seller
Key defense	Comparative or contributory fault	Limited; assumption of risk	Misuse or substantial alteration

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Evidence

Hearsay Exceptions Compared

Aspect	Present Sense Impression	Excited Utterance	Then-Existing State of Mind	Dying Declaration
Timing of statement	While or immediately after perceiving	During or soon after a startling event	At the time the state of mind exists	While believing death is imminent
Driving rationale	No time to fabricate	Stress stills reflection	Direct window into the declarant's mind	Solemnity of impending death
Declarant availability	Irrelevant	Irrelevant	Irrelevant	Must be unavailable
Subject limits	Describes the event perceived	Relates to the startling event	Cannot prove a past fact remembered	Concerns cause/circumstances of death
Case limits	Any case	Any case	Any case	Homicide or any civil case (FRE)

Impeachment vs. Substantive Use of Prior Statements

Aspect	Prior Inconsistent Statement	Prior Consistent Statement	Prior Identification
Purpose	Attack credibility (and sometimes substance)	Rehabilitate after attack	Confirm an earlier ID of a person
Hearsay status	Non-hearsay if made under oath at a proceeding	Non-hearsay to rebut recent-fabrication claim	Non-hearsay if declarant testifies and is cross-examinable
Declarant must testify?	Yes, for substantive use	Yes	Yes
Typical use	Show the witness changed the story	Show the story predates the alleged motive	Lineup or showup identification

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Constitutional Law

Levels of Constitutional Scrutiny

Aspect	Rational Basis	Intermediate Scrutiny	Strict Scrutiny
Government's interest	Legitimate	Important	Compelling
Fit of the law	Rationally related	Substantially related	Narrowly tailored / least restrictive
Burden of proof	On the challenger	On the government	On the government
Triggers	Most economic and social laws	Gender; legitimacy classifications	Race, national origin, fundamental rights
Likely outcome	Almost always upheld	Close call	Usually struck down

First Amendment Speech Categories

Aspect	Content-Based Regulation	Content-Neutral Regulation	Unprotected Speech
Standard applied	Strict scrutiny	Intermediate (time, place, manner)	Little or no protection
Focus of analysis	Targets the message itself	Regulates the manner regardless of message	Category falls outside protection
Examples	Banning a viewpoint	Noise ordinances; permit rules	Incitement, true threats, obscenity, fighting words
Required tailoring	Necessary and least restrictive	Narrowly tailored, ample alternatives	Generally regulable outright

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Agency & Partnership

Agency Authority Compared

Aspect	Actual Express	Actual Implied	Apparent	Inherent / Ratification
Source of authority	Principal's explicit instructions	Reasonably necessary to the task	Principal's manifestations to the third party	Position-based or later approval
Whose perspective controls	The agent's reasonable belief	The agent's reasonable belief	The third party's reasonable belief	Fairness to third parties / principal's choice
Principal bound?	Yes	Yes	Yes, even beyond actual authority	Yes, by position or ratification
Common scenario	“Sign this lease”	Authority to hire a needed helper	Former agent still appears authorized	Manager acts typical for the role

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Business Associations

Direct vs. Derivative Shareholder Suits

Aspect	Direct Suit	Derivative Suit
Whose injury	The shareholder's own injury	A harm to the corporation itself
Who recovers	The suing shareholder	The corporation
Standing requirements	Be an injured shareholder	Contemporaneous ownership; adequate representation
Demand requirement	None	Demand on the board (unless excused as futile)
Typical claim	Denied dividends; voting rights violated	Directors breached duties to the company

Director Fiduciary Duties & Business Judgment

Aspect	Duty of Care	Duty of Loyalty	Business Judgment Rule
What it requires	Act with reasonable prudence and diligence	Act in the corporation's best interest	Presumption that informed decisions are protected
Typical breach	Gross negligence; uninformed decisions	Self-dealing; usurping a corporate opportunity	Rebutted by fraud, bad faith, or conflict
Cleansing mechanism	Reliance on experts in good faith	Disinterested approval or entire fairness	Lost if loyalty or care is breached
Standard of review	Negligence-like inquiry	Entire fairness when conflicted	Deferential to the board

General vs. Limited vs. LLP Partnerships

Aspect	General Partnership	Limited Partnership	LLP / LLC
Personal liability	All partners personally liable	Limited partners shielded; general partner liable	Owners generally shielded
Management role	All partners may manage	Limited partners stay passive	Members may manage or appoint managers
Formation	Can arise informally by conduct	Requires a state filing	Requires a state filing
Effect of management by passive owner	Not applicable	May lose liability shield (older rule)	Management does not forfeit the shield

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Trusts & Estates

Express vs. Resulting vs. Constructive Trusts

Aspect	Express Trust	Resulting Trust	Constructive Trust
How it arises	Settlor's intentional creation	Implied to carry out probable intent	Imposed by a court as a remedy
Underlying purpose	Carry out the settlor's plan	Return property when a trust fails	Prevent unjust enrichment / wrongdoing
Requires intent?	Yes, plus a valid trust	Presumed intent	No; equitable remedy regardless of intent
Typical trigger	Written trust instrument	Purchase-money or failed gift	Fraud, duress, or breach of duty

Will Components: Codicil, Integration, Incorporation & Acts

Aspect	Codicil	Integration	Incorporation by Reference	Acts of Independent Significance
What it does	Amends or supplements a will	Treats stapled pages as one will	Pulls in an outside document	Lets outside facts fill in gifts
Must be executed with formalities?	Yes, like a will	Yes; the will itself	No, document need not be a will	No formalities for the outside act
Republication effect	Re-dates the will to the codicil	Not applicable	Document must predate or be identified	Not applicable
Example	“I now leave my car to Sam”	Multiple unstapled sheets signed once	“Distribute per my memo dated June 1”	“Contents of my safe to my niece”

Per Stirpes vs. Per Capita Distribution

Aspect	Strict Per Stirpes	Per Capita with Representation	Per Capita at Each Generation
Where division begins	Always at the first generation	At the first generation with a living taker	At the first generation with a living taker
Shares of equally-related takers	May differ by branch	May differ by branch	Equal among same-generation takers
Dropping shares	Pass down each bloodline	Pass down each bloodline	Pooled and redivided equally
Guiding idea	Honor family lines	Living root drives the split	Equality within each generation

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Civil Procedure

Personal vs. Subject-Matter Jurisdiction

Aspect	Personal Jurisdiction	Subject-Matter Jurisdiction
What it governs	Power over the parties	Power over the type of case
Can it be waived?	Yes, by consent or failure to object	No, never waivable
Raised when	Must be raised early or lost	Anytime, even on appeal
Federal bases	Minimum contacts plus fairness	Federal question or diversity
Constitutional anchor	Due Process	Article III plus statute

Diversity vs. Federal-Question Jurisdiction

Aspect	Diversity Jurisdiction	Federal-Question Jurisdiction
Core requirement	Complete diversity of citizenship	Claim arising under federal law
Amount in controversy	Must exceed $75,000	No amount requirement
Where federal law appears	May apply state law	Federal issue on the face of the complaint
Citizenship rules	Individuals by domicile; corporations dual	Not relevant to jurisdiction
Supplemental claims	Allowed if same case or controversy	Allowed if same case or controversy

Claim Preclusion vs. Issue Preclusion

Aspect	Res Judicata (Claim Preclusion)	Collateral Estoppel (Issue Preclusion)
What is barred	Relitigating the entire claim	Relitigating a specific decided issue
Same parties required?	Yes, same parties or privies	Binding party must have had a full chance
Was the issue litigated?	Need not have been actually litigated	Must have been actually litigated and essential
Final judgment needed?	Yes, valid final judgment on the merits	Yes, on the specific issue
Reach	Covers all claims that could have been raised	Limited to issues actually decided

Erie: State vs. Federal Law in Diversity

Aspect	Apply State Law	Apply Federal Law
Type of rule	Substantive rights and obligations	Procedural matters
Federal directive on point?	No valid federal rule conflicts	A Federal Rule or statute directly applies
Outcome-determinative test	Used when no federal rule controls	Federal rule controls if valid under the REA
Examples	Statutes of limitations; elements of a claim	Pleading standards; time to answer

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Criminal Procedure

Search Warrant Exceptions Compared

Aspect	Search Incident to Arrest	Automobile Exception	Plain View	Exigent Circumstances
What justifies it	A lawful custodial arrest	Probable cause plus mobility	Lawful vantage point	Emergency leaving no time for a warrant
Scope	Person and immediate grabbing area	Anywhere evidence could be in the car	Item whose incriminating nature is obvious	Limited to addressing the emergency
Probable cause required?	No, arrest alone justifies	Yes	Yes, immediately apparent	Yes, plus the emergency
Warrant needed?	No	No	No	No

Miranda vs. Sixth Amendment Right to Counsel

Aspect	Miranda (Fifth Amendment)	Sixth Amendment Right to Counsel
When it attaches	Custodial interrogation	Formal charges initiated
Offense scope	All offenses once invoked	Offense-specific
What triggers protection	Custody plus questioning	Adversary proceedings begin
Waiver	Knowing and voluntary	Knowing and voluntary
Violation remedy	Statement suppressed	Statement and lineup suppressed

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