|Minor Character: Las Vegas|
|Family|| Unnamed ex-wife|
|Portrayed By||Alex Carter|
|First Appearance||Grissom Versus the Volcano|
Detective Louis "Lou" Vartann is a homicide detective at the Las Vegas Police Department in CSI: Crime Scene Investigation.
Vartann has a son named Jake, who turned 21 during season 10. His ex-wife got custody of his son during the divorce, but his son was a handful and so Vartann got custody when his son was in high school. His son no longer lives at home, and Vartann misses having someone to come home to. ("The Panty Sniffer")
During Season 10, it is shown that Lou is having a relationship with Catherine Willows.
In "Blood Moon", Catherine and Lou are having sex with each other and then even discuss moving in with each other but Catherine says that that the relationship is moving too quick and that she would just like them to take things slower, so that they can carry on their purely sexual relationship.
Vartann believes Las Vegas has no history, that history in Vegas gets imploded. (Bang-Bang)
|CSI:Crime Scene Investigation|
- Although his full name is Louis, everyone refers to him as Lou.
- He is an alcoholic, but has been sober for over 15 years. (The List)