She is a professor at the Faculty of Law and current secretary general of the Pontifical Catholic University of Chile (PUC).

[1] She graduated in 1981 with maximum distinction, and received the Monsignor Carlos Casanueva and Luis Gutiérrez Allende awards for her academic performance and participation in activities at the PUC Faculty of Law.

[4] In 2004, Peña received a grant from the Bar Association of Chile [es] to participate in the Course on European Community Law Applied to Latin America.

[3] She has published articles related to matters of political, constitutional, and international law in several national legal journals.

During her time on the court, she stood out for her conservative positions, including votes in favor of the unconstitutionality of the distribution of Levonorgestrel (the "morning after pill") in the public health system, and the Inter-American Development Bank loan to Transantiago.