I. Foundational Common Law Doctrines
1. Stare Decisis — Courts must follow precedent established by higher courts. The backbone of common law jurisprudence and the basis of predictability in judicial decision-making.
2. Res Judicata — A matter once finally decided by a competent court cannot be re-litigated between the same parties on the same cause of action. Comprises cause of action estoppel and issue estoppel.
3. Audi Alteram Partem — No person shall be condemned unheard. A cardinal principle of natural justice requiring that every affected party be given a fair opportunity to present their case.
4. Nemo Judex in Causa Sua — No one shall be a judge in their own cause. The rule against bias, forming the second pillar of natural justice alongside audi alteram partem.
5. Ex Dolo Malo Non Oritur Actio — No action arises from fraud. A court will not lend its aid to a party whose cause of action is founded in their own fraudulent or illegal act.
6. Actus Non Facit Reum Nisi Mens Sit Rea — An act does not make a person guilty unless the mind is also guilty. The foundational doctrine of criminal law requiring both act and intention.
7. Ignorantia Juris Non Excusat — Ignorance of the law is no excuse. Every person is conclusively presumed to know the law of the land.
8. Delegatus Non Potest Delegare — A delegate cannot further delegate. A person to whom authority has been delegated cannot sub-delegate that authority unless expressly permitted.
II. Contract Law Doctrines
9. Doctrine of Consideration — A contract is enforceable only if supported by lawful consideration moving from the promisee. Bare promises are not enforceable at common law.
10. Doctrine of Privity — Only parties to a contract can sue or be sued on it. Third parties acquire no rights and bear no obligations under a contract to which they are strangers.
11. Doctrine of Frustration — A contract is discharged when a supervening event, not caused by either party, renders performance impossible, illegal, or radically different from what was undertaken. Codified in Section 56 of the Indian Contract Act.
12. Doctrine of Promissory Estoppel — Where a party makes a clear and unequivocal representation of future intention and the other party acts upon it to their detriment, the first party is estopped from resiling from that representation. In India, expanded significantly by the Supreme Court in Central London Property Trust v. High Trees and further developed domestically.
13. Doctrine of Unjust Enrichment — No person shall be allowed to enrich themselves at the expense of another without a legal justification. The foundation of restitutionary claims and quasi-contract.
14. Doctrine of Election — A party cannot simultaneously approbate and reprobate a contract. Having chosen to affirm a voidable contract, a party cannot thereafter seek to avoid it.
15. Doctrine of Anticipatory Breach — When a party repudiates a contract before the performance date, the innocent party may treat the repudiation as an immediate breach and sue without waiting for the due date.
16. Contra Proferentem — Where a contractual term is ambiguous, it shall be construed against the party who drafted or introduced it, particularly in standard form and insurance contracts.
17. Doctrine of Blue Pencil — Courts may sever an unreasonable or illegal clause from a contract while upholding the remainder, rather than striking down the entire agreement, where the offending portion can be cleanly excised.
18. Doctrine of Unconscionability — Courts may refuse to enforce a contract or a clause that is oppressively one-sided, particularly where there is a significant inequality of bargaining power between the parties.
III. Property Law Doctrines
19. Nemo Dat Quod Non Habet — One cannot give what one does not have. A transferor cannot confer on another a better title than what they themselves possess.
20. Doctrine of Part Performance — Section 53A of the TPA. A party who has taken possession in part performance of a contract for transfer of immovable property is protected from eviction by the transferor, even without a registered instrument.
21. Doctrine of Lis Pendens — Section 52 of the TPA. During the pendency of a suit involving immovable property, any transfer of that property by a party to the suit is subject to the outcome of the litigation.
22. Doctrine of Cypres — Where a charitable trust cannot be carried out as originally directed, the court will apply the trust fund to a purpose as close as possible to the original intention of the settlor.
23. Doctrine of Feeding the Grant — If a grantor conveys property which they do not own at the time but subsequently acquires, the after-acquired title automatically feeds and inures to the benefit of the grantee.
24. Doctrine of Merger — A lesser estate merges into a greater estate when both vest in the same person in the same right, extinguishing the lesser interest.
25. Rule Against Perpetuities — An interest in property must vest, if at all, within a life in being at the time of creation of the interest plus a further period. Under the TPA, the perpetuity period is a life or lives in being plus eighteen years.
26. Doctrine of Subrogation — A person who pays off a debt secured by a mortgage is substituted to all the rights of the mortgagee against the mortgagor. Codified in Section 92 of the TPA.
27. Doctrine of Tacking — A mortgagee may in certain circumstances tack a subsequent advance onto a prior mortgage so as to gain priority over an intervening mortgagee.
28. Cuius Est Solum Doctrine — Whoever owns the land owns everything above it to the sky and below it to the depths of the earth. Modified in modern law by aviation and mining legislation.
IV. Equity Doctrines
29. He Who Comes to Equity Must Come with Clean Hands — A party seeking equitable relief must themselves be free from inequitable conduct in relation to the subject matter of the suit.
30. Equity Follows the Law — Equity does not override the law but supplements it. Where the law provides a clear right, equity will not contradict it, though it may mitigate its rigours.
31. Equity Acts in Personam — Equitable remedies operate against the person of the defendant, not against the property itself. A court of equity compels conduct rather than effecting direct legal change.
32. Doctrine of Conversion — Where there is a binding contract for sale of land, equity treats the land as money in the hands of the vendor and the purchase price as land in the hands of the purchaser from the date of contract.
33. Doctrine of Satisfaction — Where a debtor makes a testamentary gift to a creditor, equity presumes that the gift is intended to satisfy the debt, absent contrary intention.
34. Doctrine of Performance — Where a person covenants to do an act and thereafter does something that substantially resembles what they covenanted to do, equity treats the act as done in performance of the covenant.
V. Tort Law Doctrines
35. Volenti Non Fit Injuria — To one who consents, no wrong is done. Voluntary assumption of a known risk is a complete defence in tort.
36. Res Ipsa Loquitur — The thing speaks for itself. Where the facts of a case raise a prima facie inference of negligence without direct proof, the burden shifts to the defendant to explain.
37. Novus Actus Interveniens — A new intervening act breaks the chain of causation between the defendant’s negligence and the claimant’s damage, absolving the defendant of liability for the subsequent harm.
38. Ex Turpi Causa Non Oritur Actio — No cause of action arises from a base or illegal cause. A claimant cannot recover damages arising from their own illegal conduct.
39. Rylands v. Fletcher Rule — A person who brings onto their land something likely to do mischief if it escapes must keep it at their peril; if they fail to do so, they are prima facie answerable for all the damage which is the natural consequence of the escape. A doctrine of strict liability.
40. Doctrine of Contributory Negligence — Where the claimant’s own negligence contributed to their damage, damages are apportioned in proportion to the respective fault of each party.
41. Thin Skull Rule (Eggshell Skull Rule) — A tortfeasor must take their victim as they find them. If the claimant has a pre-existing vulnerability that causes them to suffer greater harm, the defendant is liable for the full extent of the damage.
VI. Constitutional and Administrative Law Doctrines
42. Doctrine of Basic Structure — Propounded in Kesavananda Bharati v. State of Kerala (1973). Parliament cannot amend the Constitution so as to destroy or abrogate its basic or essential features. Among the most significant constitutional doctrines in Indian jurisprudence.
43. Doctrine of Harmonious Construction — Where two constitutional provisions or statutes appear to conflict, courts must so interpret them as to give effect to both, avoiding conflict rather than creating it.
44. Doctrine of Pith and Substance — When determining the legislative competence of a law, courts look to its true nature and character — its pith and substance — rather than its incidental encroachment on another legislature’s field.
45. Doctrine of Colourable Legislation — The legislature cannot do indirectly what it cannot do directly. Where a legislature lacks competence to enact a law on a subject, it cannot achieve the same result by enacting it under a different colourable head.
46. Doctrine of Occupied Field — Where Parliament has enacted a comprehensive law on a subject in the Concurrent List, the State legislature’s law on the same subject is repugnant to it to the extent of inconsistency under Article 254.
47. Doctrine of Eclipse — A law that was valid at the time of enactment but becomes inconsistent with a subsequently enacted fundamental right is not void but merely eclipsed. Should the fundamental right be amended or removed, the law revives.
48. Doctrine of Severability — Where part of a statute is unconstitutional, that part shall be severed and the remainder upheld, provided the valid and invalid portions are separable and the legislature would have enacted the valid portion independently.
49. Doctrine of Legitimate Expectation — A person who has been led to expect a certain procedure or benefit from a public authority by reason of a promise, practice, or established conduct has a right to be heard before that expectation is defeated.
50. Doctrine of Proportionality — Administrative action that restricts fundamental rights must be proportionate to the legitimate aim pursued. The means must not be excessive in relation to the end. Increasingly applied by Indian courts in fundamental rights jurisprudence.
51. Wednesbury Unreasonableness — An administrative decision is liable to be quashed if it is so unreasonable that no reasonable authority could ever have come to it. Adopted in Indian administrative law as a standard of judicial review.
52. Doctrine of Public Trust — Certain resources — navigable waters, coastal lands, public parks — are held by the State in trust for the public. The State as trustee cannot alienate or impair these resources in derogation of the public interest.
VII. Criminal Law Doctrines
53. Double Jeopardy — No person shall be prosecuted and punished for the same offence more than once. Guaranteed under Article 20(2) of the Constitution and Section 300 of the CrPC.
54. Doctrine of Common Intention — Section 34 of the IPC. Where a criminal act is done by several persons in furtherance of a common intention, each is liable as if they had done the act alone.
55. Doctrine of Common Object — Section 149 of the IPC. Every member of an unlawful assembly is guilty of an offence committed by any other member in prosecution of the common object of that assembly.
56. McNaghten Rules — The test for the insanity defence in criminal law. An accused is not criminally responsible if, at the time of the act, they were suffering from a disease of the mind such as not to know the nature of the act, or if they did know it, they did not know it was wrong.
57. Doctrine of Transferred Malice — Where a person intends to harm one person but accidentally harms another, the criminal intention is transferred to the unintended victim and the accused is liable as if the harm were intended.
58. Doctrine of Constructive Liability — A person may be liable for a criminal act committed by another where they share a common intention, participate in an unlawful assembly, or are in a position of command responsibility.
VIII. Evidence Law Doctrines
59. Best Evidence Rule — A party must produce the best evidence available. In documentary evidence, the original document must be produced unless its non-production is accounted for.
60. Hearsay Rule — An out-of-court statement tendered for the truth of its contents is inadmissible, subject to numerous exceptions under the Indian Evidence Act.
61. Doctrine of Estoppel — Section 115 of the Indian Evidence Act. When one person has by their declaration, act, or omission caused another to believe a thing to be true and to act upon such belief, they shall not be allowed to deny the truth of that thing.
62. Doctrine of Relevancy — Only facts that are relevant to the facts in issue are admissible in evidence. Relevancy under the Evidence Act is defined exhaustively by Sections 6 to 55.
63. Doctrine of Res Gestae — Facts that form part of the same transaction are relevant even if they are not directly the fact in issue. Covers spontaneous statements made contemporaneously with the act.
IX. Rare and Specialised Doctrines
64. Doctrine of Worthier Title — At common law, a remainder to the grantor’s own heirs was void; the heirs took by descent rather than by purchase. Largely historical but occasionally encountered in trust and estate litigation.
65. Doctrine of Destructibility of Contingent Remainders — A contingent remainder was destroyed if it did not vest at or before the determination of the preceding freehold estate. Abolished in most modern jurisdictions but relevant in historical title disputes.
66. Seisin Doctrine — In feudal property law, seisin referred to actual possession of a freehold estate. A grantor could only convey what they were seised of. Residual relevance in understanding historical title chains.
67. Doctrine of Ancient Lights — A building that has received daylight through windows for twenty years or more acquires a prescriptive right to continue receiving that light. Relevant in easement disputes.
68. Doctrine of Attractive Nuisance — An occupier of land who maintains on it a condition that is likely to attract children and is dangerous to them owes a duty of care to child trespassers who may be attracted by it.
69. Holding Out Doctrine — A person who by words or conduct represents that another is their agent is estopped from denying the agency as against third parties who have acted on that representation in good faith.
70. Doctrine of Indoor Management (Turquand’s Rule) — Persons dealing with a company in good faith are entitled to assume that the internal requirements and procedures of the company have been complied with, even if they have not been.
71. Alter Ego Doctrine (Lifting the Corporate Veil) — Courts will pierce the corporate veil and treat the company and its controllers as one where the corporate form is used as a mere cloak for fraud, evasion of obligation, or to defeat public policy.
72. Doctrine of Legitimate Defence — A person is entitled to use reasonable force to defend themselves, another person, or their property against an unlawful attack, provided the force used is proportionate and not excessive.
73. Doctrine of Hot Pursuit — Originating in public international law, it permits a state to continue pursuit of a vessel or person beyond its territorial waters or boundaries where the pursuit began within its jurisdiction. Applied by analogy in criminal procedure.
74. Last Opportunity Rule (Davies v. Mann) — Where both parties have been negligent but one of them had the last clear opportunity to avoid the accident and failed to do so, that party bears full liability. Now largely superseded by contributory negligence apportionment.
75. Doctrine of Abatement — The right of a private individual to remove a nuisance without recourse to legal proceedings. Limited in modern law and exercisable only in narrow circumstances.
76. Pristine Plus Doctrine — Developed in environmental law in the United States and increasingly referenced in Indian environmental jurisprudence — compensation for environmental damage must restore the environment to its condition before the harm and additionally address consequential losses.
77. Precautionary Principle — In environmental law, where there is scientific uncertainty about harm, the absence of full scientific certainty shall not be used as a reason for postponing measures to prevent environmental degradation. Accepted by the Supreme Court of India as part of domestic environmental law.
78. Polluter Pays Principle — The entity responsible for pollution bears the cost of remediation and compensation, regardless of intent. A strict liability standard in environmental law.
79. Doctrine of Eclipse in International Law — A rule of customary international law that has been superseded by a contrary treaty obligation is merely eclipsed, not extinguished, and revives if the treaty ceases to apply.
80. Forum Non Conveniens — A court may decline to exercise jurisdiction where another forum is clearly more appropriate for the resolution of the dispute, having regard to the interests of the parties and the ends of justice.
81. Doctrine of Renvoi — In private international law, where the law of a foreign country is applicable, the question arises whether this refers to the domestic law of that country or its entire legal system including its conflict of laws rules.
82. Doctrine of Immovables — In private international law, questions relating to immovable property are governed by the lex situs — the law of the place where the property is situated — irrespective of the law governing the transaction generally.
83. Doctrine of Subrogation in Insurance — Once an insurer indemnifies an insured, the insurer steps into the shoes of the insured and may pursue any remedy the insured had against a third party responsible for the loss.
84. Uberrimae Fidei — Insurance contracts are contracts of the utmost good faith. Both parties, but especially the insured, must disclose all material facts known to them at the time of contracting. Non-disclosure vitiates the contract.
85. Doctrine of Marshalling — Where a creditor has recourse to two funds and another creditor has recourse only to one, equity compels the first creditor to first resort to the fund against which the second creditor has no claim, so as to satisfy both.
86. Doctrine of Hotchpot — In succession law, a beneficiary who has received an advance from the deceased’s estate must bring it into account — throw it into the common pool — before claiming an equal share with others.
87. Cy-Pres Doctrine — Where the original objects of a charitable trust fail, the court will apply the trust property to purposes as close as possible to the original intent, rather than allowing the trust to fail entirely.
88. Doctrine of Ademption — Where a testator bequeaths a specific item but that item no longer exists or has been disposed of before death, the bequest fails — it is adeemed.
89. Doctrine of Lapse — Where a legatee predeceases the testator, the bequest lapses and falls into residue, unless a contrary intention appears in the will or anti-lapse legislation applies.
90. Doctrine of Exoneration — A beneficiary who takes mortgaged property under a will is entitled to have the mortgage discharged out of the general estate, unless the testator clearly intended the legatee to take subject to the mortgage.
X. International Law Doctrines
91. Pacta Sunt Servanda — Treaties must be observed in good faith. The foundational principle of international treaty law under the Vienna Convention on the Law of Treaties.
92. Jus Cogens — Peremptory norms of international law from which no derogation is permitted by treaty. Includes prohibitions on genocide, slavery, torture, and crimes against humanity.
93. Erga Omnes — Obligations owed by a state to the international community as a whole, the breach of which entitles any state to invoke responsibility, not merely the directly injured state.
94. Non-Refoulement — A state may not return a refugee or asylum seeker to a country where they face serious threats to their life or freedom. A peremptory norm under refugee and human rights law.
95. Doctrine of State Immunity — A sovereign state is generally immune from the jurisdiction of foreign courts in respect of its governmental acts, though commercial activities may attract a more limited immunity.
This index spans over ninety doctrines across ten domains of law. No practising lawyer will encounter all of them, but the truly complete legal mind knows where each doctrine lives, what problem it solves, and when to reach for it. The rarest doctrines are often the most decisive — because opposing counsel has never thought to argue against them.