Legal doctrines and principles

The internal affairs doctrine is a choice of law rule in corporations law.

Non bis in idem, which translates literally from Latin as "not twice in the same [thing]", is a legal doctrine to the effect that no legal action can be instituted twice for the same cause of action.

The Nuremberg principles were a set of guidelines for determining what constitutes a war crime.

Universal jurisdiction allows states or international organizations to claim criminal jurisdiction over an accused person regardless of where the alleged crime was committed, and regardless of the accused's nationality, country of residence, or any other relation with the prosecuting entity.

Eminent domain (United States, the Philippines), compulsory purchase (United Kingdom, New Zealand, Ireland), resumption (Hong Kong), resumption/compulsory acquisition (Australia), or expropriation (France, Mexico, South Africa, Canada, Brazil, Portugal) is the power of a state or a national government to take private property for public use.

Negligence (Lat. negligentia, from neglegere, to neglect, literally "not to pick up something") is a failure to exercise the care that a reasonably prudent person would exercise in like circumstances.

Unjust enrichment is a legal concept referring to situations in which one person is enriched at the expense of another in circumstances which the law treats as unjust.

In common law legal systems, a precedent, or authority, is a principle or rule established in a previous legal case that is either binding on or persuasive for a court or other tribunal when deciding subsequent cases with similar issues or facts.

In the criminal law of many nations, necessity may be either a possible justification or an exculpation for breaking the law.

Erga omnes is a Latin phrase which means "towards all" or "towards everyone".

Rechtsstaat is a doctrine in continental European legal thinking, originating in German jurisprudence, that can be translated as "legal state", "state of law", "state of justice", "state of rights", or "state based on justice and integrity".

Subsidiarity is a principle of social organization that originated in the Roman Catholic Church.

A constitutional convention is an informal and uncodified procedural agreement that is followed by the institutions of a state.

Res judicata or res iudicata, also known as claim preclusion, is the Latin term for "a matter [already] judged", and refers to either of two concepts: in both civil law and common law legal systems, a case in which there has been a final judgment and is no longer subject to appeal; and the legal doctrine meant to bar (or preclude) continued litigation of a case on same issues between the same parties.

Ex turpi causa non oritur actio (Latin "from a dishonorable cause an action does not arise") is a legal doctrine which states that a plaintiff will be unable to pursue legal remedy if it arises in connection with his own illegal act.

In tort law, a duty of care is a legal obligation, which is imposed on an individual requiring adherence to a standard of reasonable care while performing any acts that could foreseeably harm others.

In the law of contracts, frustration of purpose is a defense to enforcement of the contract.

Proportionality is a general principle in law which covers several special (although related) concepts.

In law, standing or locus standi is the term for the ability of a party to demonstrate to the court sufficient connection to and harm from the law or action challenged to support that party's participation in the case.

In English law, remoteness is a set of rules in both tort and contract, which limits the amount of compensatory damages for a wrong.

In private international law, the public policy doctrine or ordre public concerns the body of principles that underpin the operation of legal systems in each state.

Ignorantia juris non excusat or ignorantia legis neminem excusat (Latin for "ignorance of the law excuses not" and "ignorance of law excuses no one" respectively) is a legal principle holding that a person who is unaware of a law may not escape liability for violating that law merely because he or she was unaware of its content.

The public trust doctrine is the principle that the sovereign holds in trust for public use some resources such as shoreline between the high and low tide lines, regardless of private property ownership.

In law, economics and the social sciences, inequality of bargaining power is where one party to a "bargain", contract or agreement, has more and better alternatives than the other party.

The Fairness Doctrine was a policy of the United States Federal Communications Commission (FCC), introduced in 1949, that required the holders of broadcast licenses both to present controversial issues of public importance and to do so in a manner that was — in the Commission's view — honest, equitable, and balanced.

A legal maxim is an established principle or proposition.

Unconscionability in English law is a field of contract law and the law of trusts, which precludes the enforcement of consent based obligations.

Qui facit per alium facit per se is a Latin legal term that means, "He who acts through another does the act himself.

Vicarious liability is a form of a strict, secondary liability that arises under the common law doctrine of agency, respondeat superior, the responsibility of the superior for the acts of their subordinate or, in a broader sense, the responsibility of any third party that had the "right, ability or duty to control" the activities of a violator.