Legal Question in Technology Law in California

Yes, if it's really happening. That A was able to access B's email does not mean he was allowed to do so. With very few exceptions, willfully accessing another person's email (or any other electronic data) without permission is a crime.

This activity is illegal. I think it is covered by Penal Code section 631 which criminalizes wiretapping and gives a very broad definition of wiretapping that should include interception of e-mails not intended for that person. It might also fall under section 632, dealing with electronic eavesdropping. P.C. Section 637.2 authorizes a civil suit by anyone injured by a violation of the wiretapping or eavesdropping laws.

This crime is actually governed by Penal Code section 502, which prohibits unauthorized access to computer systems or data. I don't think it would qualify as wiretapping or electronic eavesdropping as Mr. Whipple suggests, but it might under some circumstances.

Violating section 502 can be either a misdemeanor or a felony depending upon the circumstances.

Mr. Hoffman is right. I knew there was a more specific Penal Code section, but thanks to the way the publisher organizes the index of the Code, I just couldn't find it. Nevertheless, since a civil suit would be possible under 631 and 637.2, and the definition of wiretapping seems to fit the activity, these Code provisions might be useful if the D.A. is too busy to bring a criminal action under 502.