[Footnote 148: See the _Postilion_ (1779), Hay & Marriot, 245; the _Danous_ (1802), 4 C. Rob. 255, note; the _Venus_ (1814), 8 Cranch, 253.]
§ 89. The general rule with regard to vessels is that their character is determined by their flag. Whatever may be the nationality of the owner of a vessel--whether he be a subject of a neutral State, or of either belligerent--she bears enemy character, if she be sailing under the enemy flag. For this reason, the vessel of an enemy owner which sails under a neutral flag does as little bear enemy character as the vessel of the subject of a neutral State sailing under the flag of another neutral State. But the flag is the deciding factor only when the vessel is legitimately sailing under it. Should it be found that a vessel sailing under the flag of a certain neutral State has, according to the Municipal Law of such State, no right to fly the flag she shows, the real character of the vessel must be determined in order to decide whether or no she bears enemy character. On the other hand, it makes no difference that the owner be the subject of a neutral non-littoral State without a maritime flag and that the vessel is, therefore, compelled to fly the flag of a maritime State: if the flag the vessel flies be the enemy flag, she bears enemy character.
The general rule that the flag is the deciding factor has exceptions, and it is convenient to expound the matter according to the rules of the Declaration of London, although it is not yet ratified. The general rule is laid down by article 57 of the Declaration which enacts that, subject to the provisions respecting transfer to another flag, the character of a vessel is determined by the flag she is entitled to fly. Nevertheless, there are two exceptions to this rule:--
(1) According to article 46 of the Declaration[150] a neutral merchantman acquires enemy character by taking a direct part in the hostilities, by being in the exclusive employment of the enemy government, and by being at the time exclusively intended either for the transport of troops or for the transmission of intelligence for the enemy. And it must be emphasised that the act by which a neutral merchantman acquires enemy character need not necessarily be committed _after_ the outbreak of war, for she can, even _before_ the outbreak of war, to such a degree identify herself with a foreign State that, with the outbreak of war against such State, enemy character devolves upon her _ipso facto_, unless she severs her connexion with the State concerned. This is, for instance, the case of a foreign merchantman which in time of peace has been hired by a State for the transport of troops or of war material, and is carrying out her contract in spite of the outbreak of war.[151]