Duhaime's Law Dictionary

Necessitas Indicit Privilegium Quoad Jura Privata Definition:

From necessity spring privileges upon private rights.

Related Terms: Necessity

A Latin and fundamental maxim of Roman law subsequently adopted by and now well established in the common law.

Indeed, it was expressed by Francis Bacon as follows:

"The law chargeth no man with default where the act is compulsory and not voluntary, and where there is not a consent and election; and therefore if either there be an impossibility for a man to do otherwise, or so great a perturbation of the judgment and reason as in presumption of law man's nature cannot overcome, such necessity carrieth a privilege in itself.

"Necessity is of three sorts: necessity of conservation of life; necessity of obedience and necessity of the act of God or a stranger."

Bacon even suggests that this maxim would justify a person from prosecution in the event that two persons in distress upon a body of water and both clinging to:

"... plank or on the boat's side to keep himself above water, and another, to save his life, thrust him from it whereby he is drowned, this is justifiable."

An example given by Osborne is:

“... to destroy property in the path of a conflagration to halt it, or to enter on property and damage it in time of war may be justified... [A] farmer may shoot a savage dog which is attacking his sheep.”

The maxim has been used to develop the criminal law defence of self-defence.


  • Bacon, Francis, The Elements of the Common Law of England: Maxims of the Law, from The Works of Francis Bacon, Vol. IV (London, 1826), page 33.
  • Broom, H., A Selection of Legal Maxims Classified and Illustrated (London: Sweet & Maxwell Limited, 1939), pages 8-11
  • Duhaime, Lloyd, Cannibalism on the High Seas: the Common Law's Perfect Storm (2011)
  • Osborne, P., A Concise Law Dictionary (London: Sweet & Maxwell, 1954), page 229-230

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