General average

The law of general average is a legal principle of maritime law according to which all parties in a sea venture proportionally share any losses resulting from a voluntary sacrifice of part of the ship or cargo to save the whole in an emergency (for instance, when the crew throws some cargo overboard to lighten the ship in a storm).

In the exigencies of hazards faced at sea, crew members often have precious little time in which to determine precisely whose cargo they are jettisoning. Thus, to avoid quarreling that could waste valuable time, there arose the equitable practice whereby all the merchants whose cargo landed safely would be called on to contribute a portion, based upon a share or percentage, to the merchant or merchants whose goods had been tossed overboard to avert imminent peril. While general average traces its origins in ancient maritime law, still it remains part of the admiralty law of most countries.

A form of what is now called general average was included in the Lex Rhodia, the Rhodes Maritime Code of circa 800 BC.Julius Paulus Prudentissimus quoted from the law around the turn of the 3rd century, and these quotes are preserved, and an excerpt is included in Justinian's 6th-century Digest of Justinian (part of the Corpus Juris Civilis), although the Lex Rhodia is itself now lost.

After the fall of Rome, formal maritime law fell into disuse in Europe (maritime law scholar Jean Marie Pardessus suggests that the Digest of Justinian may have been entirely lost until a copy was discovered in Amalfi around 1135), although informal arrangements similar to the basic concept of general average was probably often followed as a practical matter. The medieval Rolls of Oléron, probably a collection of judgments from a court in Bordeaux, provided (along with much else) guidance on what is now called general average, and was taken as authoritative in many parts of Europe: the Laws of Wisbuy, as well as laws of Flanders, the Hanseatic League, Amsterdam, Genoa, and Catalonia, appear to have been copied from the Rolls of Oléron.

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