Assertor
Assertor or ADSERTOR is the name given to the party who asserts or vindicates in an action (liberale judicium) the freedom of another (Gaius, 4.14); for a person who claimed to be free could not sue on his own behalf. By the law of the Twelve Tables it was enacted in favour of liberty, that an adsertor should not be called on to give security in the sacramenti actio to more than the amount of 50 asses. In the course of the action the adsertor laid his hand on the person whose liberty he claimed (adsertus), and formally asserted the right of the latter to his freedom. Hence adserere in libertatem, liberali adserere manu. (Ter. And. 2.1, 40; Plaut. Poen. 4.2, 83.)
The expression adserere in servitutem, to claim a person as a slave,
occurs in Livy (3.44; 34.18). The vindicatio in libertatem was employed as a collusive action for the purpose of manumitting slaves (manumissio per vindictam). In later times the part of assertor was represented by the Praetor's lictor. (Dig. 40. 12, de Liberali Causa; Cod. 7.16.)
From William Smith (ed.), Dictionary of Greek and Roman Antiquities. Text provided under a CC BY-SA license by Perseus Digital Library, http://www.perseus.tufts.edu, with funding from the National Endowment for the Humanities and Tufts University. Data accessed from https://github.com/PerseusDL/canonical-pdlrefwk/ on 17 October 2026.