Mr. Marquez has practiced law in Colorado since 1986, and began private practice with the Salida Law Office in 1990. A graduate of the University of Colorado School of Law, he served with the Office of the Public Defender in Colorado from 1986 to 1990, in the Arapahoe County office, and Chaffee County office.

Prior to Law School, he was awarded a Bachelor of Music degree from the University of Houston in 1977 as a performance major. He has played the french horn semi-professionally, and continues to play and perform today.

Professional organizations include the Colorado Bar Association (past member of the Executive Council), Colorado Criminal Defense Bar, National Association of Criminal Defense Lawyers, and is a current member, and Past President of the Heart of the Rockies Bar Association.

Other activities include a position on the Board of Directors of the Colorado Legal Services, President of the Alpine Orchestra, and membership in the Rotary Club of Salida.