In California, if you are injured on the property of another person (for example, at someone elses' home or at a place of business) you must usually show that the property owner "knew" or "should have known" that the cause of your injury was a dangerous condition that the property owner could have warned about or remedied. However, if the property owner actually created the dangerous condition, then this notice is presumed. Furthermore, in the case of a retail or commercial property, notice can be presumed if the property owner did not have a regular practice or procedure for inspection of the property for dangers. The bottom line is that this requires a good attorney who can conduct the proper investigaiton for you and determine if you have a case.