From the Spyderco website:
Spyderco Civilian G-10
In the 1990s Spyderco was approached by a specialized branch of U.S. law enforcement about making a knife for their undercover agents. These plain-clothes LEOs found themselves in situations where they often could not carry a firearm but carrying a knife was not a problem. Most had no formal training in self-defense tactics or MBC but as a last resort could use a blade to protect or extricate themselves from a life-threatening situation. This was how the Civilian model came to be.
They also have the same blade that is about an inch shorter overall (1/2" in the blade and 1/2" in the handle) called the Matriarch.