Bio, via DHS.Gov:

Prior to joining DHS, Christina served in the United States Marine Corps as a Judge Advocate. During her time on active duty, she was as an operational law attorney in Helmand Province, Afghanistan, assisting the Command in all legal matters relating to operations and intelligence. While stationed in Quantico, Virginia, Christina worked as a defense counsel, representing marines and sailors in courts-martial and administrative separation hearings. Christina also mobilized to Marine Corps Forces Europe and Africa in Stuttgart, Germany as an operations officer. In this role, she was responsible for briefing the senior leadership on current operations in both Europe and Africa on a daily basis. In addition to her military service, Christina spent several years as a civil litigation attorney, representing clients in all stages of trial, negotiations, mediations, and arbitration at the law firm Higgs, Fletcher, & Mack LLP in San Diego, California. Most recently, Christina clerked at the Office of Legal Counsel for the White House Office of National Drug Control Policy. Christina holds a B.A. from Arizona State University, an M.B.A. from San Diego State University, a J.D. from California Western School of Law, and an L.L.M. in National Security Law from Georgetown University Law Center.