Criminal Law

1

Actus non facit reum nisi mens sit rea

An act does not make a person guilty unless the mind is also guilty

Foundation of criminal liability — requires both actus reus (wrongful act) and mens rea (guilty mind) to establish a crime

2

Ignorantia juris non excusat

Ignorance of law is no excuse

A person cannot avoid liability by claiming unawareness that their conduct was illegal

3

Nemo debet bis vexari pro una et eadem causa

No one should be vexed twice for the same cause

Basis of the principle against double jeopardy (Article 20(2), Indian Constitution)

4

Actio personalis moritur cum persona

A personal right of action dies with the person

Relevant when the injured party dies and legal action's continuation is in question

Contract Law 1

Pacta sunt servanda

Agreements must be kept

Once a valid contract is formed, parties must honor its terms; central to breach of contract and specific performance

2

Ex nudo pacto non oritur actio

No action arises from a bare agreement

Relates to the necessity of consideration; an agreement without consideration is generally unenforceable, except exceptions like Section 25, Indian Contract Act

3

Consensus ad idem

Meeting of the minds

Both parties must share the same understanding of contract terms; absence can void a contract due to fundamental mistake

4

Caveat emptor

Let the buyer beware

Places responsibility on the buyer to check goods before purchase; diluted by modern consumer protection laws

Tort Law

1

Ubi jus ibi remedium

Where there is a right, there is a remedy

Underpins the entire law of torts — every legal right must have a corresponding remedy if violated

2

Volenti non fit injuria

To a willing person, no injury is done

Defense in tort law — voluntary consent to risk bars later claims for damages

3

Res ipsa loquitur

The thing speaks for itself

Used in negligence cases where the nature of the accident implies negligence, shifting burden of proof to the defendant

4

Damnum sine injuria

Damage without legal injury

Loss or harm suffered without violation of a legal right — no remedy available

5

Injuria sine damno

Legal injury without actual damage

A violated legal right allows remedy even without real harm — e.g., Ashby v. White

Evidence & Procedure

1

Audi alteram partem

Hear the other side

Principle of natural justice ensuring no person is condemned unheard

2

Nemo judex in causa sua

No one should be a judge in their own cause

Second pillar of natural justice, ensuring impartiality and preventing bias

3

Onus probandi

The burden of proof

The party asserting a fact generally bears the burden of proving it

4

Falsus in uno, falsus in omnibus

False in one thing, false in everything

Suggests a lying witness is unreliable throughout — largely rejected as a rigid rule by Indian courts

Justice & Equity

1

Salus populi suprema lex

The welfare of the people is the supreme law

Laws should serve the greater good, invoked in public interest and emergency powers

2

Ex turpi causa non oritur actio

No action arises from an immoral or illegal cause

Courts won't assist a claim based on an illegal act

3

De minimis non curat lex

The law does not concern itself with trifles

Explains why courts don't entertain trivial matters

4

Delegatus non potest delegare

A delegate cannot further delegate

In administrative law — delegated authority cannot be passed on further unless expressly permitted

5

Nova constitutio futuris formam imponere debet, non praeteritis

A new law ought to regulate the future, not the past

Principle against retrospective application of laws, protected under Article 20(1), Indian Constitution