[1] Her father, Juan María Begué Arjona, was a property registrar who was murdered in the first months of the Spanish Civil War in October 1936.

[2] Cantón grew up in La Bañeza and gained her Spanish Baccalaureate at the Instituto Padre Isla de León.

[1] She refused to teach an exclusive group of female students and was surprised at her request to reside at the Colegio Mayor de Santiago el Zebedeo.

[6][7] She was later elected vice-president of the Constitutional Court of Spain during its plenary session in which she received eight votes and four blank ballots on 4 March 1986.

[8] Cantón was rapporteur in more than 100 judgements such as the right to work; presumption of innocence; conscientious objection; the draft Organic Law on the Harmonization of the Autonomous Process; the partial decriminalization of abortion; the Coat of arms of Navarre; the application of tax regulations; bank savings; university autonomy;[1] and the expropriation of Rumasa.

[2] Cantón was considered to be a more ideologically conservative member of the court,[3] and ceased to be a magistrate when her nine-year term ended in February 1989.

[4] She taught courses on the European Union in the Jean Monnet Chair, the legal-constitutional aspects of economic relations in doctoral and postgraduate programs.

She was chair of the Management Board of the Institute of International Issues and the Independent Association Foundation of the Senate; was a member of the European Institute of Spain; the Committee of Experts of Expo '92; Council for the Debate on the Future of the European Union and was on the jury of the Prince of Asturias Awards in the Social Sciences in 1998.

[12] On 27 February 1989, Cantón was decorated with the Dame Grand Cross of the Order of Isabella the Catholic by Juan Carlos I.