LEGAL REASONING Thecommonlaw,whichismadebycourts,consistsofrules thatgovernrelationsbetweenindividuals,suchastorts(the law of private wrongs) and contracts. Legal Reasoning explains and analyzes the modes of reasoning utilized by thecourtsinmakingandapplyingcommonlawrules.These modes include reasoning from binding precedents (prior cases that are binding on the deciding court); reasoning from authoritative although not binding sources, such as leading treatises; reasoning from analogy; reasoning from propositionsofmorality,policy,andexperience;reasoning from hypotheticals; making exceptions; drawing distinc- tions; and overruling. The book further examines and explainstherolesoflogic,deduction,andgoodjudgment inlegalreasoning.Withaccessibleproseandfulldescrip- tionsofillustrativecases,thisbookisavaluableresource for anyone who wishes to get a hands-on grasp of legal reasoning. MelvinA.EisenbergisJesseH.ChoperProfessorofLaw Emeritus,University ofCalifornia, BerkeleyLaw School. HeistheauthorofTheNatureoftheCommonLawand FoundationalPrinciplesofContractLaw. Published online by Cambridge University Press Published online by Cambridge University Press Legal Reasoning Melvin A. Eisenberg UniversityofCalifornia,Berkeley Published online by Cambridge University Press UniversityPrintingHouse,CambridgeCB28BS,UnitedKingdom OneLibertyPlaza,20thFloor,NewYork,NY10006,USA 477WilliamstownRoad,PortMelbourne,VIC3207,Australia 314–321,3rdFloor,Plot3,SplendorForum,JasolaDistrictCentre, NewDelhi–110025,India 103PenangRoad,#05–06/07,VisioncrestCommercial,Singapore238467 CambridgeUniversityPressispartoftheUniversityofCambridge. ItfurtherstheUniversity’smissionbydisseminatingknowledgeinthepursuitof education,learning,andresearchatthehighestinternationallevelsofexcellence. www.cambridge.org Informationonthistitle:www.cambridge.org/9781009162524 DOI:10.1017/9781009162517 ©MelvinA.Eisenberg2022 Thispublicationisincopyright.Subjecttostatutoryexception andtotheprovisionsofrelevantcollectivelicensingagreements, noreproductionofanypartmaytakeplacewithoutthewritten permissionofCambridgeUniversityPress. Firstpublished2022 AcataloguerecordforthispublicationisavailablefromtheBritishLibrary. ISBN978-1-009-16252-4Hardback ISBN978-1-009-16250-0Paperback CambridgeUniversityPresshasnoresponsibilityforthepersistenceoraccuracyof URLsforexternalorthird-partyinternetwebsitesreferredtointhispublication anddoesnotguaranteethatanycontentonsuchwebsitesis,orwillremain, accurateorappropriate. Published online by Cambridge University Press ToHelen Published online by Cambridge University Press Published online by Cambridge University Press CONTENTS Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page ix 1 ABriefIntroductiontotheCommonLaw . . . . . . . . . . . . 1 2 Rule-BasedLegalReasoning. . . . . . . . . . . . . . . . . . . . . . 5 3 ReasoningfromPrecedentandthePrincipleofstaredecisis 13 4 HowItIsDeterminedWhatRuleaPrecedentEstablishes 25 5 ReasoningfromAuthoritativeAlthoughNotLegally BindingRules. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 6 TheRoleofMoral,Policy,andEmpiricalPropositions inLegalReasoning,andtheJudicialAdoptionofNewLegal RulesBasedonSocialPropositions . . . . . . . . . . . . . . . . . 41 7 LegalRules,Principles,andStandards . . . . . . . . . . . . . . 60 8 TheMalleabilityofCommonLawRules. . . . . . . . . . . . . . 64 9 HivingOffNewLegalRulesfromEstablishedLegal Rules,CreatingExceptionstoEstablishedRules, andDistinguishing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 10 Analogy-BasedLegalReasoning . . . . . . . . . . . . . . . . . . . 82 11 TheRolesofLogic,Deduction,andGoodJudgment inLegalReasoning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 12 ReasoningfromHypotheticals. . . . . . . . . . . . . . . . . . . . . 90 13 Overruling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 vii Published online by Cambridge University Press Published online by Cambridge University Press PREFACE Thisprefaceprovidesanoverturetothechaptersofthisbook. Chapter 1. An Introduction to the Common Law. One of two legal systems prevails in most developed economies: common law or civil law.Incivillawsystemsthelawisfoundinstatutes,executivedecrees, andCivilCodes–codificationsofthelawofobligations,property,and family. In common law systems public law, which concerns such matters as the organization of government, is made by legislatures and administrative agencies while private law, which concerns such mattersastherelationshipbetweenindividuals,islargelymadebythe courts.Thepurposeofthisbookistoexplainandanalyzelegalreason- inginthecommonlaw. Chapter 2. Rule-Based Legal Reasoning. Common law courts have two functions: resolving disputes according to legal rules and making legal rules. A common law rule is a relatively specific legal norm, established by the courts, that requires persons to act or not act in a specified way; enables or disables specified types of arrangements, suchascontracts,anddispositions,suchaswills,orspecifiesremedies fordesignatedwrongs.Reasoninginthecommonlawisalmostentirely rule-based–thatis,basedontheapplicationoflegalrulestothefactsof thecasetobedecided.Legalreasoninginthecommonlawisoccasion- ally but infrequently analogy-based and is almost never similarity- based. Chapter3.StareDecisis.Thefoundationofrule-basedreasoninginthe commonlawistheprincipleofstaredecisis,aLatinphrasewhichmeansto standbythingsdecided.Undertheprincipleofstaredecisiswhenacourt decidesacasethatisgovernedbyaruleestablishedinaprecedent–aprior ix https://doi.org/10.1017/9781009162517.001 Published online by Cambridge University Press