Elle was formerly assigned to FBI Field Office in Seattle, Washington;
then requested to be assigned to the BAU. She is an expert in sex crimes. Her father was a New York City Police Officer but was killed in the line of duty. She is half Cuban and speaks Spanish. After she was shot in the Season 1 finale, she returned to the BAU rather quickly, against the advice of the rest of the team. Not long after, she staked out and shot a serial rapist in cold-blood because of his crimes against women (2x05 - The Aftermath). Her ability to continue work as a profiler was questioned by Hotch and...
Elle: Chemical accelerant could mean chemistry student.
Reid: It could also mean chemistry professor.
Elle: I say student. You need self-confidence to lecture in front of a classroom full of 30 college kids. Arsonists are socially incompetent. This guy doesn’t go on dates, doesn’t go to parties, doesn’t feel comfortable in front of groups. [Reid looks at Elle] And of course he’s a total psychopath.
Reid: Of course.
Elle: Well, what is the most sinful place on campus?