What's a ministerial duty?
A ministerial duty is one which an officer or tribunal performs in a given state of facts, in a prescribed manner, in obedience to the mandate of a legal authority, without regard to or the exercise of his own judgment upon the propriety or impropriety of the act done. (Spouses Marquez v. Spouses Alindog, 725 Phil. 237, 249. 2014)