California law defines ordinary negligence as the failure to use reasonable care to prevent harm to oneself or to others.

A person is negligent if he or she:

  • Does something that a reasonably careful person would NOT do in the same situation, or
  • Fails to do something that a reasonably careful person WOULD do in the same situation.

Thus the basic issue for a jury in negligence cases is what a reasonably careful person would do under the same or similar circumstances if the person owed the plaintiff a duty of care. And did the defendant’s breach of legal duty cause the plaintiff’s injury?