Spanish canonist, librarian of the University of Salamanca, deputy during the Trienio Liberal (Liberal Triennium) and introducer of Kant and Benthan in Spain.

He studied in the Royal Studies of San Isidro and in the University of Salamanca. He reinforced his legal training at the Royal Academies of Theology, Ecclesiastical Law and Canons. Ascribed to the most reformist group of the cloister, he was protected by Meléndez Valdés and collaborated with Ramón de Salas. His links with Meléndez grew after he married the niece of Meléndez's wife, Cándida de la Riba Coca.

Núñez failed in his attempt to obtain an academic post; although he occupied some professorships on an interim basis, he did not manage to pass any of the competitive examinations he sat. In 1798, he decided to move to Sevilla as administrator of the assets of the Duchess of Alba, also working as a merchant. In 1804, he moves to Piedrahíta as he was getting married for the second time, this time to Teresa Somoza Carvajal, sister of José Somoza. During this period he was Trustee Attorney for the noble state of the municipality of Piedrahita. In 1812, he returns to Salamanca obtaining the position of University's Senior Librarian. After Ferdinand's VII return, he was part of the commission that was to report on the public education project. However, his situation at the University changed as a result of the inspection of the institution to monitor the spread of pernicious ideas. He was prosecuted, expelled and interned in the Consiliar Seminary of Salamanca. Later on, he moved to Piedrahita where he spent his life writing about Bentham's work.

He was rehabilitated during the Trienio Liberal (Liberal Triennium) obtaining then the deputy position. As member of the Permanent Commission he voted in favour of the destitution of Ferdinand VII which had major consequences on him after the intervention of the Hundred Thousand Sons of Saint Louis. He returned to Sevilla where he lived in a precarious economic situation due to the impossibility of collecting their royalties, among other things.

Moreover, he was the one who introduced Kant's school of thought that he tried to reconcile with Bentham's contributions.