Samuel is recognized by Chambers Latin America and Latin Lawyer as a leading constitutional law practitioner. He focuses on constitutional law and human rights.
He has been a member of the Constitutional Reform Commission appointed by the Transition Government (2001), and has been part of the specialists' team that prepared the Draft for the Code of Constitutional Procedure Code (2003). He was also the Secretary General of the National Tribunal for Civil Service, Coordinator of the Area for Democratic Institutions in the Andean Commission of Jurists, Assistant on Constitutional Matters and First Assistant to the Public Ombudsperson.
He is the author of many articles and essays on human rights, constitutional law, and constitutional procedural law and has published several books, and is a regular speaker at several national and international seminars. Chambers & Partners states that "is a famous figure in constitutional law". Likewise, Latin Lawyer has expressed that is an "Excellent lawyer that have a very important experience in litigation", besides "experience in constitutional law".
Samuel focuses his practice on constitutional law and human rights and has extensive experience in litigation.