From the AMA:

The California State Senate followed the State Assembly’s lead in passing California SB 142. AMA spoke out in opposition to this bill in a letter to the Senate and the bill’s sponsors, and testified further before the Joint Legislative Committee on Emergency Management and the Senate Judiciary Committee on August 18th. Despite these efforts the California legislature passed SB 142, legislation that may pose a significant threat to recreational model aviation.
While originally intended to address privacy concerns the bill was amended in late June and, as such, now potentially subjects model aviation enthusiasts to possible law suits and civil sanctions for even an inadvertent excursion over the property of a neighbor that borders their flying field, schoolyard, park, or even their backyard.
This bill currently is sitting on Governor Brown’s desk waiting for his action. Time is short. The governor has until September 12, 2015 to either sign or veto this proposed legislation.
Please act now and let Governor Brown know that, as a recreational aeromodeler, you believe that this bill is too broad and overreaching and can only have a negative impact on model aviation.
Thanks for your help on this important issue.
http://amagov.modelaircraft.org/18534/californiasb142/