Law of majestas

The Law of treason, or lex maiestatis, refers to any one of several ancient Roman laws (leges maiestatis) throughout the republican and Imperial periods dealing with crimes against the Roman people, state, or Emperor.

In Roman law the offences originally falling under the head of treason were almost exclusively those committed in military service. The very name perduellio, the name of the crime in the older Roman law, is evidence of this. Perduelles were, strictly, public enemies who bore arms against the state; and traitors were regarded as having no more rights than public enemies. The Twelve Tables made it punishable with death to communicate with the enemy or to betray a citizen to the enemy. Other kinds of perduellio were punished by "interdiction of fire and water" (aquae et ignis interdictio), in other words, banishment. The crime was tried before a special tribunal (quaestio) by two officials (duumviri perduellionis), which was perhaps the earliest permanent criminal court existing at Rome.

At a later period the name of perduellio gave place to that of laesa maiestas, deminuta or minuta maiestas, or simply maiestas. The lex Iulia maiestatis, to which the date of 48 B.C. has been conjecturally assigned, continued to be the basis of the Roman law of treason until the latest period of the empire. The original text of the law appears to have still dealt with what were chiefly military offences, such as sending letters or messages to the enemy, giving up a standard or fortress, and desertion.

With the empire the law of treason was greatly expanded in scope, mainly in the reign of Tiberius, and led to the rise of a class of professional informers, called delatores. The concept of the emperor as divine had much to do with this. It became a maxim that treason was next to sacrilege in gravity.

The law as it existed in the time of Justinian is contained chiefly in the titles of the Digest and Codex Ad legem Iuliam maiestatis. The definition given in the Digest (taken from Ulpian) is this: ''maiestatis crimen illud est quod adversus populum Romanum vel adversus securitatem eius committitur." ("The crime of majestas is that which is committed against the Roman people or against their safety.") Of treasons other than military offences, some of the more noticeable were the raising of an army or levying war without the command of the emperor, the questioning of the emperor's choice of a successor, the murder of (or conspiracy to murder) hostages or certain magistrates of high rank, the occupation of public places, the meeting within the city of persons hostile to the state with weapons or stones, incitement to sedition or administration of unlawful oaths, release of prisoners justly confined, falsification of public documents, and failure of a provincial governor to quit his province at the expiration of his office or to deliver his army to his successor.

...
Wikipedia