What is the initial burden of producing evidence in a personal injury case?

Moreover, as a practical matter, facts material to judicial resolution of the case, e.g., whether the conservator is acting in good faith and based upon medical advice, are peculiarly within the knowledge of the conservator, and it is not unfair to impose the initial burden on the conservator to produce evidence on these matters. (See People v. Montalvo (1971) 4 Cal.3d 328, 334 [noting rule of necessity and convenience, whereby initial burden of producing evidence may be placed on the party who has more ready access to proof of a fact peculiarly within his knowledge]; 7 Cal. Law Revision Com. Rep., supra, pp. 89-90.)