Liberum veto

![Jean II Casimir (1609-1672) après avoir échoué à abolir le liberum veto en 1665[3], abdique en 1668 pour terminer sa vie en France](/uploads/202501/24/Bacciarelli_-_Jan_Kazimierz2014.jpeg)
The liberum veto (Latin for "the free veto") was a parliamentary device in the Polish–Lithuanian Commonwealth. It was a form of unanimity voting rule that allowed any member of the Sejm (legislature) to force an immediate end to the current session and nullify any legislation that had already been passed at the session by shouting Sisto activitatem! (Latin: "I stop the activity!") or Nie pozwalam! (Polish: "I do not allow!"). The rule was in place from the mid-17th to the late 18th century in the Sejm's parliamentary deliberations. It was based on the premise that since all Polish noblemen were equal, every measure that came before the Sejm had to be passed unanimously. The principle of liberum veto was a key part of the political system of the Commonwealth, strengthening democratic elements and checking royal power, going against the European-wide trend of having a strong executive (absolute monarchy).