Lawyer from the Externado de Colombia University. He has two post graduate degrees, a master's degree and a doctorate in Law from the same institution.

He has developed his professional career in both public and private sectors, where he has held positions related to the three branches of public power and control organizations from the estate.

Prior to being elected as a Constitutional Court´s judge, Dr. Fernández served as Legal Secretary of the Presidency of the Republic, First Delegate Attorney before the Council of State, Secretary General of the National Federation of Departments, as well as a consulting lawyer for public organizations such as the Mayor's office of Bogotá, the Government of Boyacá, the Regional Autonomous Corporation of the Río Grande del Magdalena, the General Contralory of the Republic and the Ministry of Education.

He is a professor in the undergraduate law program and in postgraduate program at the Universidad Externado de Colombia where he has also worked as a monitor and researcher. He obtained Honors during all five years of his undergraduate studies.

He is the author of several academic texts, among which stands out the book called Arbitrability of contractual administrative acts and the articles titled: Political Death due to Parliamentary Absenteeism and the administrative act against the precautionary measures of the Arbitrators in Colombia.