Public Political Agents.
§ 453. Public political agents are agents sent by one Power to another for political negotiations of different kinds. They may be sent for a permanency or for a limited time only. As they are not invested with diplomatic character, they do not receive a Letter of Credence, but a letter of recommendation or commission only. They may be sent by one full-Sovereign State to another, but also by and to insurgents recognised as a belligerent Power, and by and to States under suzerainty. Public (or secret) political agents without diplomatic character are, in fact, the only means for personal political negotiations with such insurgents and States under suzerainty.
As regards the position and privileges of such agents, it is obvious that they enjoy neither the position nor the privileges of diplomatic envoys.[797] But, on the other hand, they have a public character, being admitted as public political agents of a foreign State. They must, therefore, certainly be granted a special protection, but no distinct rules concerning special privileges to be granted to such agents seem to have grown up in practice. Inviolability of their persons and official papers ought to be granted to them.[798]
[797] Heffter, § 222, is, as far as I know, the only publicist who maintains that agents not invested with diplomatic character must nevertheless be granted the privileges of diplomatic envoys.
[798] Ullmann, § 66, and Rivier, I. § 40, maintain that they must be granted the privilege of inviolability to the same extent as diplomatic envoys.
Secret Political Agents.
§ 454. Secret political agents may be sent for the same purposes as public political agents. But two kinds of secret political agents must be distinguished. An agent may be secretly sent to another Power with a letter of recommendation and admitted by that Power. Such agent is a secret one in so far as third Powers do not know, or are not supposed to know, of his existence. As he is, although secretly, admitted by the receiving State, his position is essentially the same as that of a public political agent. On the other hand, an agent may be secretly sent abroad for political purposes without a letter of recommendation, and therefore without being formally admitted by the Government of the State in which he is fulfilling his task. Such agent has no recognised position whatever according to International Law. He is not an agent of a State for its relations with other States, and he is therefore in the same position as any other foreign individual living within the boundaries of a State. He may be expelled at any moment if he becomes troublesome, and he may be criminally punished if he commits a political or ordinary crime. Such secret agents are often abroad for the purpose of watching the movements of political refugees or partisans, or of Socialists, Anarchists, Nihilists, and the like. As long as such agents do not turn into so-called agents provocateurs, the local authorities will not interfere.
Spies.
§ 455. Spies are secret agents of a State sent abroad[799] for the purpose of obtaining clandestinely information in regard to military or political secrets. Although all States constantly or occasionally send spies abroad, and although it is neither morally nor politically and legally considered wrong to send spies, such agents have, of course, no recognised position whatever according to International Law, since they are not agents of States for their international relations. Every State punishes them severely when they are caught committing an act which is a crime by the law of the land, or expels them if they cannot be punished. And a spy cannot legally excuse himself by pleading that he only executed the orders of his Government. The latter, on the other hand, will never interfere, since it cannot officially confess to having commissioned a spy.
[799] Concerning spies in time of war, see below, [vol. II. §§ 159] and [210], and Adler, "Die Spionage" (1906), pp. 7-62.