Abstract
Causal uncertainty is frequently encountered in medical malpractice cases, both in China and in other legal systems. Under the traditional “all-or-nothing” approach of proof rules, the prevalence of causal uncertainty makes proof of causation highly problematic in medical malpractice lawsuits. The cutting-edge development at the national level is to apply proportional liability in response to evidentiary uncertainty over causation. After examining both “law on the books” and “law in action” pertaining to medical malpractice, it is found that although the new Chinese Tort Liability Law lacks evident rules that handle the problem of causal uncertainty, Chinese courts are so active and flexible that they systematically employ proportional liability to the trial of medical malpractice cases. The proportional liability approach can be justified from both legal and law and economics perspectives.

I. Introduction

 In recent years, there is a growing public awareness of the seriousness of conflicts or disputes between health care providers and patients over the cause of iatrogenic injury (negligence or non-negligence) and/or the amount of compensation for iatrogenic injury (hereinafter medical disputes) in the People’s Republic of China. Comprehensive empirical studies in China show that medical disputes are prevalent and is becoming more frequent. However, what often grabs the headlines more is widespread violence against health care providers. A series of nationwide empirical studies show that about 56.1%~63.7% of the surveyed physicians are physically threatened or injured, and roughly 35.58%~96% of the surveyed hospitals’ property and order are disturbed or damaged by patients, their family members or “professional mobs” (职业医闹). Whereas many violent incidents occur because discontented patients abruptly lose control of their emotions, a significant proportion of violent incidents are attributable to patients’ deliberate strategies for claiming damages from hospitals by coercive measures. Protest and violence are routinely used as “a common tool for patients and their family members seeking compensation from hospitals. The plausible explanation of why patients resort to violence in order to claim compensation is that they do not trust the legal system that resolves medical disputes. This “lack of a credible system” rather than frivolous litigation or unavailability of malpractice insurance becomes the real “malpractice crisis” in China.

Much legislative endeavor has been made in order to build a credible malpractice system in China. The medical malpractice liability system was formally established in China in the second half of the 1980s, and has been drastically reformed twice since then. Voluminous literature regarding the Chinese malpractice liability reforms is currently available in English. In general, most scholarly discussions were centered on three main reforms: the criteria for liability, the expert witness system (鉴定制度) and the measure of compensation. First, the MHMA and the RHMA imposed some restrictions on the standard of care, causation, and compensatory damage – all of which have been eliminated altogether. The current standard of care required of physicians is defined as the “obligations of diagnosis and treatment up to the standard at the time of the diagnosis and treatment.” Second, the old expert witness system created by the MHMA was criticized for “protectionism, monopoly and lack of transparency,” which has been replaced by a new expert witness system based on the RHMA. In practice, the RHMA-based system, which mainly relies on doctors practicing clinical medicine, intensely competes with the alternative medico-legal judicial authentication system under which forensic physicians produce expert evidence. Available empirical evidence shows that expert testimony is critical to the resolution of medical disputes and expert witnesses give the vast majority of proof of medical liability. This “battle of experts” between clinical doctors and forensic physicians greatly increases legal uncertainty. Unfortunately, the TLL does not touch on this debatable issue. Third, the limitations imposed on the measure of compensation by the MHMA and the RHMA have been entirely removed. Currently, the measure of compensation for iatrogenic injuries applies the same rules - art. 16 TLL for pecuniary losses and art. 22 TLL for non-pecuniary losses - as that of compensation for other types of personal injuries does.

No matter how the malpractice system varies, the proof of liability is the starting point and critical to a successful claim. All requirements of malpractice liability – fault, causation and damage – must be established before the plaintiff-patient can obtain any compensation. As far as the requirements are concerned, although the TLL has evidently defined the standard of care (art. 57 TLL) and the scope of compensatory damage (art. 16, art. 22 TLL), it keeps causation issues unaddressed; so did the prior legislation.

However, proof of causation is particularly difficult in medical malpractice cases. At least two factors can contribute to evidential uncertainty and dispute over causation (“causal uncertainty”). First, there is evident informational asymmetry between medical professionals and patients (and judges). Compared to physicians who are experts in medical science and who actually perform treatment, patients as medical laymen normally know little about pathology and only have an intuitive sense of what happens during treatment. The information concerning causation may be available to defendant-hospitals, but it may not be available to patients or judges for various reasons. Sometimes, patients “may have been under anesthetic and unable to observe what was done to him.” Sometimes, the most important type of evidential material – medical records – are forged or destroyed by the defendant or simply missing. Neither patients nor judges are able to establish causation in the absence of crucial evidentiary documents. Sometimes, it is not difficult to prove that the injury is caused by at least one but not all of the doctors’ or hospitals’ faults, but it is factually indeterminate as to which doctor or hospital is the real tortfeasor.

Second, it is not infrequent in some medical cases that even medical experts are unsure whether or to what extent an injury was caused by the negligent treatment. There are hard cases where there is “scientific uncertainty concerning the causal relationship” between a faulty treatment and an iatrogenic injury. Even equipped with the most advanced medical knowledge and the state-of-the-art technology, expert witnesses often find it difficult to prove causation with certainty in cases where non-tortious factors are involved. Besides faulty treatments, injuries suffered by patients may result from two non-tortious factors: (1) the normal outcome of the patient’s underlying or pre-existing medical condition, and (2) therapeutic risks inherent in treatment beyond physicians’ control. It is indeterminate whether or which part of the final injury is attributable to the negligent treatment. In practice, a significant proportion of medical cases involve scientific uncertainty and are quite difficult cases to resolve.

Because of causal uncertainty, many patients, even with the help of expert witnesses, often find it virtually impossible to provide adequate evidence that can satisfy the traditional standard of proof. In short, causal uncertainty may make proof of causation highly problematic. In 2012, Professor Ken Oliphant examined and evaluated the TLL’s approach to uncertain (alternative) causes. According to some of Oliphant’s Chinese colleagues, “as yet little attention has been paid to” the issue of causal uncertainty. After reading the text of the TLL, Oliphant argued that, “by providing a general solution only to the problem of ‘alternative’ or ‘indeterminate’ defendants and restricting itself to an all-or-nothing approach, the new Chinese Tort Liability Law lags behind cutting-edge developments at national level.” However, a lack of a comprehensive set of rules concerning uncertain causes in the TLL does not necessarily mean that there are no medical cases involving causal uncertainty in practice. It is thus interesting to know how Chinese courts handle causal uncertainty issues in practice, and how these practical approaches can be justified.

Before answering these questions directly, it is necessary to find out how causation is commonly defined in tort law and what proof rules apply to civil dispute cases in China (Section Ⅱ). Section Ⅲ attempts to categorize medical cases involving causal uncertainty in order to facilitate further discussions and evaluations. Then, attention is paid to how Chinese legislation and courts handle causal uncertainty issues in medical malpractice cases and how the courts’ approaches can be legally justified (Section Ⅳ). Thereafter, the proportional approaches to causal uncertainty issues are evaluated from the perspective of law and economics (Section Ⅴ). The final section concludes that it is the TLL rather than the judicial practice in the field of medical malpractice in China that lags behind the latest development in other countries.