If it was indeed a ricochet, what negligence are you alleging on the part of the shooter?
If ricochets are even a possibility, then the negligence was on the part of the group or government that decided to hold a shooting event there.
RULES & REGULATIONS
CFR= Code of Federal Regulations
PC= CA Penal Code
F&G= CA Fish and Game Code
No shooting without an adequate backstop and clear visibility {43 CFR 8365.1-4(a)(2), PC 372}
Select the base of a substantial hill or crosswise canyon bottom, and give serious consideration to downrange safety, including ricochets and potential illegal alien trails hidden in the brush.
No gross negligent shooting (PC 246.3)
Any person who willfully discharges a firearm in a grossly negligent manner which could result in injury or death to a person is guilty of a public offense.
http://www.blm.gov/ca/st/en/fo/palmsprings/Target_Shooting_and_Hunting_Information.html