A veterinarian who on his or her own initiative, at the request of an owner, or at the request of someone other than the owner, renders emergency treatment to a sick or injured animal at the scene of an accident shall not be liable in damages to the owner of that animal in the absence of gross negligence.
Source:
Section 4826.1, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=BPC§ionNum=4826.1..