Legal Studies cheat sheet

Civil law systems rely on comprehensive codes; common law systems rely on judicial precedent plus statutes; mixed systems combine both.

Stare decisis: a court must follow holdings of higher courts in the same appellate hierarchy; dicta are not binding.

Ratio decidendi is the binding legal reasoning of a decision; obiter dictum is non-binding commentary.

Substantive law defines rights and duties; procedural law governs how claims are enforced.

Public law regulates the state-citizen relationship (constitutional, criminal, administrative); private law governs relations between persons (contract, tort, property).

Burden of proof: criminal cases require proof beyond a reasonable doubt; civil cases require a preponderance of the evidence (or clear and convincing in some matters).

Legal positivism: law is valid by its source; natural law theory: validity depends on moral content; legal realism: outcomes reflect judicial behavior.

Equity developed separate courts of chancery; equitable remedies (injunction, specific performance) are discretionary and historically unavailable where damages are adequate.

A precedent can be distinguished where material facts differ, overruled by a higher court, or reversed on appeal.

Hierarchy of authority: constitution > statute > regulation > case law interpreting each; a lower source conflicting with a higher source is invalid.

A constitution establishes government structure and limits power; constitutional provisions are typically harder to amend than statutes.

Judicial review lets courts invalidate acts inconsistent with the constitution; its scope varies by jurisdiction.

Plain-meaning rule: interpret statutory text by ordinary meaning first; resort to legislative history only if text is ambiguous.

Expressio unius: listing specific items implies exclusion of unlisted ones; ejusdem generis: general terms are limited to the class of listed specifics.

Regulations issued under delegated authority are valid only within the scope of the enabling statute; they have the force of law.

A repeal by implication is disfavored; the later, more specific statute controls over the earlier, general one.

Case law fills gaps and interprets text; holdings bind lower courts in the same hierarchy, persuasive authority binds no one.

Retroactive statutes are disfavored, and constitutional prohibitions on ex post facto laws apply to criminal statutes.

Subject-matter jurisdiction is the court's power over the type of case; it cannot be waived and can be raised at any time.

Personal jurisdiction requires minimum contacts plus fair play and substantial justice (for US-style analysis); in rem jurisdiction acts on property.

Venue is the proper geographic location; it is distinct from jurisdiction and can generally be waived.

Removal transfers a case from state to federal court when federal jurisdiction exists; remand sends it back.

Pleadings give notice of claims; a motion to dismiss for failure to state a claim tests legal sufficiency.

Discovery devices: interrogatories, depositions, requests for production, requests for admission; scope is typically relevance plus proportionality.

Summary judgment is granted when no genuine dispute of material fact exists and the movant is entitled to judgment as a matter of law.

Preclusion: claim preclusion bars relitigating the same claim; issue preclusion bars relitigating an issue actually litigated and necessary to judgment.

Appellate courts review legal questions de novo and factual findings for clear error; jury findings are reviewed for sufficiency of evidence.

Elements of a crime: actus reus (voluntary act or omission where a duty exists) plus mens rea (mental state) plus concurrence plus causation of harm.

Mens rea levels (Model Penal Code): purposely, knowingly, recklessly, negligently; each element's required level must be proved.

Fourth Amendment-style rule: searches require a warrant supported by probable cause, subject to exceptions (consent, plain view, search incident to arrest, exigency).

Exclusionary rule suppresses evidence obtained in violation of constitutional rights; fruit-of-the-poisonous-tree doctrine extends suppression to derivative evidence.

Miranda-type warnings are required before custodial interrogation; silence alone cannot be used as substantive evidence of guilt.

Defenses: alibi, justification (self-defense requires reasonable belief in imminent unlawful force), excuse (insanity, duress), and lack of mens rea.

Insanity tests differ: M'Naghten (did not know wrongfulness), irresistible impulse, and MPC substantial-capacity standard.

Double jeopardy bars retrial after acquittal and multiple punishments for the same offense; it does not bar retrial after mistrial or hung jury.

Sentencing must comply with statutory ranges; proportionate and non-cruel punishment limits apply under constitutional norms.

Formation requires offer, acceptance, consideration, and mutual assent; some contracts also require writing under a statute of frauds.

An offer must manifest present intent to be bound and be definite; it terminates by revocation, rejection, lapse, or death of the offeror.

Mirror-image rule: common law acceptance must match the offer; UCC-style sale-of-goods rules permit additional terms under conditions.

Consideration is a bargained-for exchange; past consideration and illusory promises are generally insufficient.

Statute of frauds categories typically include land sales, suretyship, marriage consideration, contracts not performable within one year, and goods over a threshold amount.

Material breach excuses the non-breaching party's performance; minor breach permits damages but not suspension.

Remedies: expectation damages (benefit of the bargain), reliance, restitution; consequential damages require foreseeability.

Liquidated damages are enforceable if reasonable and a genuine estimate of anticipated loss; otherwise they are an unenforceable penalty.

Defenses to enforceability: incapacity, duress, undue influence, misrepresentation, mistake, unconscionability, and illegality.

Negligence elements: duty, breach, causation (actual and proximate), and damages.

Duty is generally owed to foreseeable plaintiffs; landowner duties vary by entrant status (invitee, licensee, trespasser).

Breach is measured against the reasonable person standard; professionals are held to a customary standard of care.

Res ipsa loquitur permits an inference of negligence where the instrumentality was in the defendant's exclusive control and the event ordinarily does not occur without negligence.

Comparative negligence reduces recovery by the plaintiff's share; contributory negligence is a complete bar in jurisdictions retaining it.

Strict liability applies to abnormally dangerous activities and defective products; product liability theories include manufacturing defect, design defect, and failure to warn.

Intentional torts: battery (harmful/offensive contact), assault (apprehension of imminent contact), false imprisonment, trespass, conversion, defamation.

Defamation requires a false statement of fact, publication, fault, and harm; public figures must prove actual malice.

Damages: compensatory (special and general), punitive (for egregious conduct), and nominal; joint and several liability may apply.

Estates in land: fee simple absolute (full ownership), life estate (measured by a life), and leasehold estates (term of years, periodic tenancy, tenancy at will).

Concurrent ownership: joint tenancy includes right of survivorship; tenancy in common does not; tenancy by the entirety applies to spouses in some jurisdictions.

Deeds require identification of parties, description of land, intent to convey, and delivery plus acceptance; recording statutes protect subsequent purchasers.

Recording types: race, notice, and race-notice; a race-notice statute protects a subsequent purchaser who records first without notice.

Adverse possession elements: actual, open and notorious, exclusive, continuous, and hostile possession for the statutory period.

Easements are nonpossessory rights of use; they may be appurtenant or in gross, created by express grant, implication, necessity, or prescription.

A lease transfers a possessory interest; the covenant of quiet enjoyment protects against interference with possession.

Implied warranty of habitability requires residential premises to be fit for human habitation; retaliatory eviction is prohibited.

Security deposits are governed by statutes limiting amount and requiring return or itemized deductions within a set period.

Marriage requires capacity, mutual consent, and compliance with licensing and solemnization formalities; common-law marriage requires cohabitation plus holding out in recognizing jurisdictions.

Marital property regimes: community property (property acquired during marriage is shared equally) versus equitable distribution (fair, not necessarily equal).

Premarital agreements are enforceable if voluntarily executed with disclosure and without unconscionability.

Divorce grounds: no-fault (irretrievable breakdown, incompatibility) or fault-based (adultery, cruelty, desertion).

Child custody standards use the best interests of the child, weighing stability, caregiver relationships, and safety; joint legal and physical custody are distinct.

Child support follows statutory guidelines based on income shares and number of children; modification requires a substantial change in circumstances.

Adoption requires termination of parental rights or consent, plus a home study and court approval; the best-interests standard governs.

Paternity may be established by presumption (marriage), acknowledgment, or genetic testing; rebuttable presumptions apply.

Domestic violence protective orders may be ex parte initially and become long-term after notice and hearing.

Agency: a principal grants authority to an agent; authority may be actual (express or implied) or apparent; undisclosed principals may be liable on contracts.

Partnership: general partners share profits, management, and joint and several liability; limited partners are liable only to the extent of their investment.

Corporations are separate legal persons with limited shareholder liability; directors owe duties of care and loyalty; the business judgment rule presumes informed good-faith decisions.

Securities law prohibits insider trading and requires registration or an exemption for public offerings; materiality and scienter are key elements.

Employment at will permits termination for any lawful reason, subject to statutory and public-policy exceptions.

Title VII-type protections prohibit discrimination based on race, color, religion, sex, and national origin; retaliation and hostile-environment claims are cognizable.

Minimum wage, overtime, and child labor standards derive from wage-and-hour statutes; independent contractor status depends on control and economic-reality tests.

Workers' compensation is a no-fault system providing scheduled benefits in exchange for tort immunity of the employer.

Trade secrets and non-compete agreements are enforceable only to the extent reasonable in duration, geography, and scope.

Competence and diligence: a lawyer must provide competent representation, keep abreast of changes in the law, and prepare adequately.

Confidentiality protects all information relating to representation; the attorney-client privilege is narrower and covers confidential communications for legal advice.

Conflicts of interest: concurrent conflicts require informed consent confirmed in writing where permitted; former-client conflicts are governed by substantial relationship tests.

Duty of candor to the tribunal prohibits presenting false evidence or false statements of law and requires correcting prior false statements.

Fees must be reasonable; contingent fees are generally permitted except in criminal and certain domestic-relations matters.

Client funds must be held in trust (IOLTA-type accounts) segregated from the lawyer's own funds; commingling is prohibited.

Advertising must not be false or misleading; solicitation of prospective clients in person or by real-time contact is restricted.

Withdrawal requires court permission in litigation and must avoid material prejudice; a lawyer must return unearned fees.

Prosecutors must disclose exculpatory evidence; defense counsel may not knowingly present perjured testimony but must withdraw if the client insists.