By the Treaty of Washington, 1922, between the United States, Great Britain, France, Italy and Japan, a merchantman must not be destroyed unless the crew and passengers have been first placed in safety, and if the submarine cannot capture a merchantman in conformity with the rules applicable to other war vessels, it must permit the merchantman to proceed unmolested. Violation of these rules will be deemed an act of piracy and the plea of superior orders will be no defence. These provisions have not been ratified by France.
Unneutral Service.—A neutral individual is of course guilty of unneutral service who breaks blockade or carries contraband. But there are certain acts of a particularly distinctive service to which the term unneutral service is usually applied. These are divided into two classes by the Declaration of London according to the gravity of the act. In the first is included service which is only partial. By Art. 45 when a neutral vessel is engaged to carry military persons or despatches, concurrently with employ ment of an innocent character, she is liable to be treated in the same manner as a neutral vessel engaged in the carriage of con traband. The vessel may be condemned and the cargo if it be longs to the owner of the vessel. These are sometimes described as analogues of contraband, and so she will be treated through out as a neutral vessel. But a neutral vessel which identifies her self with the enemy falls into the second class: she is definitely guilty of "hostile service." By Art. 46, a neutral vessel is liable to be treated as an enemy merchantman (I) if she takes a direct part in the hostilities; (2) if she is under the orders or control of an agent placed on board by the enemy Government ; (3) if she is in the exclusive employ ment of the enemy Government; (4) if she is exclusively engaged at the time either in the transport of enemy troops or in the trans mission of intelligence in the interests of the enemy. In these cases goods belonging to the owner of the vessel are liable to con demnation with the vessel. By Art. 47, an individual liable to military service found on board a neutral vessel may be made a prisoner of war; and by Art. 12 of The Hague Convention X., 5907, enemy sick or wounded found on board neutral hospital or merchant ships may be removed.
During the World War the German Government having re moved all persons liable to military service from the occupied territories of Belgium and France, Great Britain in Dec. declared they would no longer be bound by Art. 47 of the Decla
ration, and that they would arrest all reservists found on board neutral vessels. This action was avowedly by way of reprisal. Nevertheless neutral states protested that such persons were not actually incorporated in the armed forces of the enemy and so not within Art. 47. This is probably true, but apart from the Declaration, persons of military age returning to their country of origin for the purpose of military service are really "noxious persons," who, if found on board neutral ships bound to an enemy port or even to a contiguous neutral port, may be seized.
Inviolability of Postal The Hague Convention XI. of 1907 the postal correspondence of both neu trals and belligerents, whatever its official or private character may be, found on board a neutral or enemy ship is inviolable. If the ship is detained the correspondence must be forwarded by the captor at once. These provisions do not apply to correspond ence destined for, or proceeding from a blockaded port. This right to inviolability does not exempt a neutral mail ship from the laws and customs of maritime war. The ship, however, may not be searched except when absolutely necessary, and then only with as much consideration and expedition as possible. Apart from the Convention neutral mail ships and other vessels carry ing mails, even though the property of a neutral Government, are not by international law exempt from the ordinary process of the tribunals of a belligerent, unless expressly exempted by treaty. Thus, such vessels are still subject to visit and search.
During the World War, Hague Convention XI. did not apply since it had not been ratified by some of the belligerents. Never theless in the first year of the war the Allied Powers did not in terfere with the mails found on neutral vessels. But when it was discovered that the Germans were sending contraband through the post and more particularly by means of the parcels post, they insisted upon the right of search and seizure. In their pro test against this policy the United States admitted 'that there was a distinction between such articles as bonds and other securities which might be regarded as merchandise, and shipping documents and money-order lists which should be regarded as genuine cor respondence. By such a distinction a right of censorship was obviously implied, but such a censorship on the high seas, owing to German submarine methods, was impracticable.