Legal Question in Employment Law in California

Yes. Unless you have a union or personal services contract you can be fired in California at any time for any reason, or none at all, except you can't be fired because of a protected classification such as race or gender, or for being a whistle blower on a protected topic. As long as it is not based on prohibited discrimination of some kind, any firing is legal. The only relevance of whether it is a termination for just cause is you can't collect unemployment if you are fired for just cause.

The answer is "no," you cannot be legally terminated for that reason. California Labor Code section 432.7 amended effective 2014 prohibits public and private employers from making inquiry into arrests not resulting in a conviction. Also, AB 218 effective July 1, 2014, bars public sector employers from asking about criminal records on employment applications (a so-called "ban the box" law).

You voluntarily disclosed that you were "charged." So technically, the "no inquiry into arrests" rule is not violated. But the issue is whether the use of the arrest information, even if voluntarily given, can support a case in employment law known as "wrongful termination in violation of public policy." That issue hasn't been tested by a reported decision interpreting Section 432.7, but the policy can be inferred from Section 432.7 that California wants both accused (arrested) and even convicted persons to have a decent opportunity of rehabilitation by re-employment. The basic rule of law is that the "public policy" in a "wrongful termination in violation of public policy" must be derived from the Constitution, a statute, or a regulation. So far, so good.

But the defense may argue that the policy is not "fundamental and well established," -- additional criteria that must be satisfied in a "wrongful termination in violation of public policy" case. The counter argument is that it has long been a constitutionally recognized principle of law that anyone can be arrested, but the Government must prove its case against a standard of presumed innocence. Your argument would gather force particularly if the charge, arrest, and even a conviction (if there is one) had no adverse impact or relevance to the work you performed for this employer.