Carrying a Concealed Firearm (Penal Code 25400)
It is a crime to carry a concealed firearm capable of being hidden on your person, either on your body or inside a vehicle you control, without a license. Prosecutors have to prove the firearm was substantially concealed and that you knew it was there.
As a misdemeanor, a conviction carries up to one year in county jail and a fine of up to $1,000.
It becomes a wobbler, meaning the prosecutor can file it as a felony, if either of two things is true. The first is a prior conviction for a misdemeanor against a person or property, or for a narcotics or dangerous drug offense. The second is that the firearm was loaded, or ammunition was readily accessible, and you're not listed with the California Department of Justice as the registered owner. That second trigger catches a lot of people who did nothing more aggressive than borrow a family member's gun.
As a felony, the exposure is 16 months, two years, or three years, and a fine of up to $10,000. If you have a prior felony conviction or a prior firearm offense, a conviction carries a minimum of three months in custody.

