Need California case laws where injury to a child resulting from an
incident of punishment was deemed to be an accident and not child
abuse.  Don't need pc 273 or 11165 languages.  I just need references
to the tried cases.  FYI, the injury in this case was nothing more
than a slight bruise on the wrist.  Orange County CPS took an
exception and found child abuse was substantiated.

The facts in any case would be specific to that case. 

The state has to prove its case - and the bruise is a prima facia (on
the face of it) case.  You, or rather your attorney, can refute the
state's case.  Then a judge or jury would decide, if it gets that far.