A native of Guadalajara, Mexico, Rosas was a lawyer, educator, businessman and engineer, before joining St. Mary’s. He has been a Visiting Professor at the St. Mary’s University School of Law since 1994 and Instructor of Law since 2000. He teaches courses in Comparative Law: Mexico and the United States and Current Legal Aspects of Doing Business with Mexico. Rosas has taught law at the Universidad de Guadalajara School of Law as a Tenure Track Professor, where he graduated at the top of his class.

Rosas worked for various law firms in Guadalajara and later, he established a solo practice. He has worked as a consultant to the Mexican government on public administration projects, the CEO of a business consulting firm, a business manager, an industrial engineer and a canon lawyer. He has lectured in the United States, Spain and Mexico, and is the author of numerous law review articles over the law of these countries that have been published in countries of the Americas, Europe, Asia, Africa and Oceania.

He was elected director of the Commission on Legal Affairs for the Advisory Council of the Institute of Mexicans Living Abroad, where his main role is advising the President of Mexico in the design and formulation of the public policies concerning the Mexican communities in the United States and Canada. In February 2014, at the headquarters of the National Human Rights Commission in Mexico City, Rosas was elected president of the Centro de los Mexicanos en la Globalización (Center for Mexicans in the Globalization).