She became a special needs teacher and enrolled at the University of Texas at El Paso,[3] studying physical therapy and social work.

She also guest-starred as an evil Kryptonian (named "Aethyr" in promotional materials) in the Season 5 premiere episode of Smallville and played the recurring role of Marisol Delko Caine on the CBS television series CSI: Miami.

In 2006, she joined the cast of NBC's Law & Order during the premiere of Season 17, portraying Assistant District Attorney Connie Rubirosa.

Rubirosa, who had recently departed the Los Angeles District Attorney's Office, is now a federal prosecutor, heading up a joint task force on underage sex trafficking.

In July 2011, de la Garza reprised her role as Marisol Delko Caine,[9] on CSI: Miami's season 10 premiere.

[12][13] In June 2012, de la Garza was added to the cast of Are You Here, the feature film debut of Mad Men creator Matthew Weiner.

[23] She is a distant cousin of TV writer-producer René Balcer, sharing a common relative in Juan Cortina, a Mexican folk hero known as the "Rio Grande Robin Hood".