Standard of proof

The standard of proof establishes the threshold for understanding that certain factual proposition is proven or not (Larroucau, 2012, p. 783). This proposition can be formulated by the plaintiff or by the defendant and, therefore, provides ex ante information to both parties about when their factual narratives will be understood as accepted in the final judgment.

The standard of proof is useful because it allows for the distribution of the risk of error. This encompasses the risk of over-inclusion, that is, the risk of punishing people who are innocent (Type I error cost), and the risk of under-inclusion, that is, the risk of acquitting people who are guilty (Type II error cost). A comparatively higher standard implies that more evidence is necessary to convict someone, which leads to fewer convictions and a higher risk of Type II error; meanwhile, a comparatively lower standard implies that less evidence is necessary to convict someone, which leads to more convictions and a higher risk of Type I error (Carrasco, 2019, pp. 702-706).

Normally, standards of proof have been examined based on the probabilities of having a certain statement proven. In this regard, it is common to use a scale ranging from 0 (signaling a very low probability of occurrence of the proposition) to 1 (signaling a high probability of occurrence of the proposition).

Thus, the criminal standard of conviction know as “beyond a reasonable doubt” implies a high probability of occurrence, whose notation is P>0.99; whereas the civil standard of preponderance of evidence, the proposition that is more probable than its alternative prevails, and has a notation of P>0.5; and, the intermediate standard of clear and convincing proof is expressed as P>0.75 (Grunberg and Montt, 2010, p. 80).

The standard of proof corresponds to a stage of evidentiary activity that follows the evaluation of evidence, whose function is to determine the degree of support that a proposition or hypothesis about the facts acquires from the evidence presented in the process. In this way, it measures the degree of probability of occurrence of those factual propositions or hypotheses. Therefore, the valuation of evidence alone does not determine whether the hypothesis is proven or not, because the degree of probability of the statement may or may not satisfy the threshold of the standard of proof. In other words, it is different to determine how probable it is that something happened, to determine if that probability is enough to determine, in legal terms, that it happened.

In this sense, the lower that threshold is, the more likely it is that those hypotheses presenting a high degree of confirmation can be deemed proven. As we will see, in contentious antitrust proceedings, the system of evidence valuation is that of sound criticism (sana crítica), which provides the court with flexibility to weigh the degree of confirmation and support received by the different hypotheses regarding the facts that make up the merits of the case.

Returning to the description of the three standards of proof, it should be noted that the standard of conviction beyond a reasonable doubt applies in criminal matters, according to Article 340 of the Criminal Procedure Code (Carnevali and Castillo, 2011, pp. 77-118); the preponderance of evidence standard applies in civil matters (despite its lack of express recognition in Chile, this standard can be derived from Article 428 of the Civil Procedure Code); and the clear and convincing evidence standard applies in antitrust, as stems from a uniform series of judgments by the Honorable Court for the Defense of Free Competition (TDLC) and the Most Excellent Supreme Court.

Clarity regarding the standard of proof applicable in contentious antitrust proceedings began to be delineated with the Farmacias (Pharmacies) case, which concluded in the first instance with Judgment No. 119/2012, where the applicability of a criminal standard of proof was ruled out. Thus, the Honorable TDLC stated: “this Court, in order to rule out any doubt that may still exist regarding the existence of the collusive agreement subject to the claim, will analyze below —with additional background— whether the behavior observed in the market is compatible with the hypothesis of mere oligopolistic interdependence or can only be explained by the hypothesis of collusion. Should the latter be concluded, the existence of the denounced collusion would have been proven beyond a reasonable doubt; that is, with a level of conviction characteristic of a standard of proof higher than what is required in this jurisdiction” (Judgment No. 119/2012 of the H. TDLC, January 31, 2012, Recital 167).

The Supreme Court, in hearing the appeals (recursos de reclamación) against the aforementioned judgment, reaffirmed the understanding that we are in the presence of a non-criminal standard of proof, that is nonetheless somewhat higher than the civil procedural standard. In this sense, it ruled that: “the measure of conviction required by this Court to sanction a case of collusion is the existence of clear and convincing evidence, which derives from the nature of the sanction and its concrete significance” (Judgment of the Most Excellent Supreme Court, September 7, 2012, Case Rol No. 2.578-2012, Recital 11).

Subsequently, a series of other final judgments issued by the H. TDLC and the Most Excellent Supreme Court have reiterated the same criterion.

Although there is no formal definition of the “clear and convincing” (or “consistent,” as noted in some judgments) standard of proof, it is possible to state that this standard can coexist with the existence of a reasonable doubt (otherwise, it would correspond to the criminal standard of proof).

Likewise, by applying the clear and convincing standard of proof, it is possible to reach a decision in favor of a hypothesis for conviction even when there is a smaller amount of evidence presented than that which has been proven in favor of the hypothesis for acquittal. This is because, through the weighing of evidence through sound criticism (sana crítica), the H. TDLC or the Most Excellent Supreme Court may assign greater weight or credibility to a smaller amount of evidence in favor of a conviction hypothesis than to a larger amount of evidence in favor of acquittal.

Finally, it should be noted that in Judgment No. 160/2017 of the H. TDLC, Justices Javier Tapia and Jaime Arancibia argued in a concurring opinion (voto de prevención) that the standard of proof in antitrust matters corresponded to a standard of preponderance of evidence or balance of probabilities.

To conceptualize this standard of proof, the concurring opinion resorted to Taruffo, concluding that: “…the judge must weigh the evidence of the case as a whole to determine if the occurrence of a substantial, pertinent, and controversial fact is more probable than not and, in the event that it is, if the factual hypothesis relative to its illegality is more probable than other hypotheses or narrative statements of the fact that dismiss its unlawfulness and, therefore, allow for the acquittal of the accused” (Judgment No. 160/2017 of the H. TDLC, December 28, 2017, Recital 27). They based this on dogmatic, economic, and institutional reasons. However, this criterion has not been followed by subsequent decisions.