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Adjusting legal standards


This paper seeks to explore whether the interpretation of legal standards is influenced by decision-makers’ substantive decision. Prior literature on motivated reasoning has shown that decision-makers “shift” their perception of evidence in their desired direction. To the extent this logic applies to legal-standards, we should expect decision-makers to adjust the perception of the legal standard accordingly—e.g., one’s decision to favor the plaintiff would induce a pro-plaintiff interpretation of the required threshold to win a case. We present the results of two experiments in which we asked subjects to report their interpretation of the applicable legal threshold after deciding a case, under different legal thresholds. Our participants, by and large, did not shift the legal standard to conform to their substantive decision, contrary to the theoretical expectations. We thus conclude that decision-makers treat the legal standard distinctly than regular evidence.

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Fig. 1


  1. 1.

    The basic paradigm which explains how people’s motivational needs, self-interest or coherent, affect decision-making is Motivated Reasoning (Kunda 1990).

  2. 2.

    We discuss these findings in detail below. See infra Sect. 4.1 and Table 5.

  3. 3.

    In translation from Hebrew, we told our participants that: “The law requires that the plaintiff would show that his version is more probable than the defendant’s. In what level should a judge be confident in the plaintiff’s version to decide for the plaintiff? Express your answer in percentage terms from 0% (no need to believe that the plaintiff is right) to 100% (need to be completely convinced that the plaintiff is right).”

  4. 4.

    For this group, we changed the first part of the relevant wording, supra note 3, in the following way: “The law requires that in order for the plaintiff to proceed beyond the preliminary phase, the plaintiff should present enough facts to state a claim for relief, which is plausible on its face.”

  5. 5.

    For this group, we changed the first part of the relevant wording, supra note 3, in the following way: “… to proceed beyond the preliminary phase, the plaintiff should present enough facts to state a claim for relief that does not seem to be frivolous.”

  6. 6.

    The online platform, Panel4All, available at, recruits paid participants that represent the general population (based on the following criteria: gender, age, religiousness, and district). We also guaranteed that, in each survey, our participants have not taken part in our previous experiments.

    We would like to stress that the three legal standards we used are familiar in the Israeli legal system. The preponderance standard is the general standard under Israeli civil law. Likewise, the “plausible on its face” standard is quite similar to a pre-requisite to exempt indigent plaintiffs from filing fees. Court Rules (Court Fees), 2007, § 14(c) (Isr.). The “frivolous” criterion is used, for instance, as a consideration for fee-shifting. Rule 514 to the Rules of Civil Procedure, 1984, K.T. 5685, 2288 (Isr.).

  7. 7.

    Lawyers translated the preponderance of evidence standard to ~ 65%, and the two preliminary standards to ~ 50%.

  8. 8.

    Specifically, the victim in this vignette suffered a severe deterioration to his (low) mental capacity. The family claimed that the victim fell from his bed at night, and they based their claim on the fact that the victim was rushed to a hospital to conduct an unscheduled computed tomography of his brain the day after the alleged fall.

  9. 9.

    Specifically, the agreement included an obligation to provide a parking lot, and the plaintiff argued that the seller, the defendant/contractor, promised him a roofed parking lot. The contractor argued, in response, that the price the plaintiff paid for the parking lot reflects regular, rather than roofed, parking.

  10. 10.

    To avoid incentives to skip the second part, we clarified that those who decide to dismiss will also have to fill a survey in the second part in order to get their reward. For a more detailed description see infra note 16.

  11. 11.

    We also asked subjects to answer comprehension questions following the vignette (and before deciding), and eliminated participants who failed to show sufficient understanding—we filtered out those who did not answer correctly half or more of the comprehension questions, in both t1 an t2.

  12. 12.

    As mentioned in the text, we used two different vignettes (a tort case and a business dispute). We also slightly changed the factual description in each vignette. The differences in the factual background between (and within) the two experiments are immaterial to the general trend that our findings depict. Therefore, we decided to collapse the reported results. As discussed before, we also collapsed the “plausibility” and the “non-frivolousness” standards for dismissal, as they were perceived as indistinguishable.

  13. 13.

    One could expect to observe different confidence levels among those who dismissed and those who did not. A decision not to dismiss defer the final judgment to t2, while a decision to dismiss ends the case and seems harder to take. (We elaborate on this issue below, infra notes 16–17 and accompanying text).

  14. 14.

    We did find several statistically significant (or marginally significant) correlations between demographic characteristics and the interpreted standard in the benchmark group (N = 183)—age is positively correlated with the stated standard, while gender (men) and higher education were negatively correlated. In the dismissing/not-dismissing sample (N = 217), and after adding the variables that indicate dismissing, perceived merits, and confidence, the demographic variables are no longer significant.

  15. 15.

    As a side note, we think that it is more plausible to believe that decision affects the stated standards in our experiments and not the other way around. First, the participants reported their perception of the standard immediately after deciding the case, suggesting the direction for causation. Second, the demographic characteristics seem to predict the decision on the merits better than the stated standard.

  16. 16.

    At the dismissal stage our instructions read as follows (translated from Hebrew, emphasis added): “The defendant asks to dismiss the case at the outset. You are the judge assigned to the case, and you have to decide now whether the case should be dismissed at the outset. Dismissals occur in preliminary stages. If you decide not to dismiss now, you will be presented next week with additional information, including relevant testimonies, with which you will decide the case. If you decide to dismiss the case at this stage, the plaintiff loses the entire case. Whether you decide to dismiss or not, you will be asked to participate next week in the second part of this survey, after which you will receive your reward.”

  17. 17.

    There are several other possible conjectures for this asymmetry. The proposition that those who dismissed did not shift the standard relate to the comparison to those who interpreted the standard in the abstract, no-decision condition. To the extent participants particularly exaggerate the standard in the abstract, such a comparison might mask an upward shift among those who dismissed. Relatedly, the decision to dismiss seems to be an unusual decision, as it eliminates access to court in preliminary stages (and only 28 participants decided to dismiss). These characteristics might render the numerical assessment of the dismissal standard particularly difficult in the abstract.

  18. 18.

    More precisely, Phillips (2002) manipulated the timing of the question to rate the standard—before or after deciding “on the merits,” and the numbers in the text refer to the post-decision interpretation of the standard. Our research examines the post-decision interpretation of the standards, and compares it to a benchmark, no-decision group that rated the standard in the abstract.

  19. 19.

    Another relevant study is Glöckner and Engel, who show experimentally that those who decided to convict in a criminal case reported a lower standard, in numerical terms, than those who decided to acquit (Glöckner and Engel 2013, pp. 242–43). The change is ~ 5.4 percentage points. Glöckner and Engel did not compare the post-decision perceptions of the standards to a benchmark, no-decision group, and did not control for the correlation between the subjective strength of the case and the participants’ demographic characteristics to the reported interpretation of the standard.

    In another relevant research, Scurich finds evidence of a small shift in the legal threshold following a decision. This work, though, studies the implicit threshold, inferred from participants’ decision on the merits and their responses regarding the strength of the case, rather than the explicit, reported numerical interpretation of the threshold (Scurich 2012, pp. 68–106).

  20. 20.

    As before, we used two vignettes with some modifications within the vignettes. Supra notes 8–9, 12 and accompanying text. For the preliminary information given to the participants at the first stage see supra notes 8–9. In the tort case, the additional information at the second stage included the following: the plaintiff presents the opinion of a medical expert who indicated that the plaintiff’s mental deterioration was sudden—which may have stemmed from a fall. The victim’s family also presents testimonies regarding the victim’s tendency to wake up at night, which should allegedly have prompted the nursing home to take extra care. The nursing home’s staff conceded that the victim suffered from a severe mental deterioration, and that he was taken care of according to the regular procedures (and no extra care was taken). Nonetheless, the nurses asserted that no special events occurred; that the victim’s deterioration results from natural fluctuations in his mental condition; and that he was taken to a computed tomography of his brain as part of a routine, but non-scheduled check up.

    In the business dispute, the additional information included the following: the plaintiff’s partner testifies that the contractor promised the plaintiff that the parking lot would be in the building, i.e., a roofed parking lot. The plaintiff provides evidence that he paid for the parking in cash, hence, allegedly he received a discount, paying less than the usual price for a roofed parking. The contractor concedes that he offered a parking in the building, but he asserts that he indicated that the parking lot will be at the top of the building, i.e., unroofed. The contractor’s employees present evidence that suggests that no other tenant received a discount on the price of a roofed parking, even for paying cash, and that the roofed parking has a fixed price (above the sum that the plaintiff paid).

  21. 21.

    We attempted to design the additional information at t2 (supra note 20) as neutral. Hence, the difference in the proportion of pro-plaintiff decisions at t1 and t2 seems to result from the more onerous standard at t2, indicating that our subjects generally managed to implement different standards.

  22. 22.

    The second column shows, in essence, that those who rejected the case thought that it is weaker (35%) than those who accepted (76%); this difference is statistically significant (t(349) = 18.0). The third column shows that people who rejected (M = 3.74, SD = 0.7) or accepted (M = 3.67, SD = 0.7) the case did not differ in a statistically significant way with respect to their decision confidence (t(349) = − 0.81, n.s.).

  23. 23.

    In Fig. 1 in the Introduction we demonstrated the same data graphically.

  24. 24.

    We note here that the additional information at t2 was designed to be neutral, with an equal number of evidence that support each side. Supra notes 20-21.

  25. 25.

    We do not think that the foregoing alternative explanation fully describes the lower standards reported by those who had a previous, conflicting decision at t1. First, as Table 6 suggests, rejectors at t2 reported overall a lower standard when they were forced to take a decision at t1, i.e., in the treatment group. Second, as Table 7 suggests, among the rejectors at t2 in the treatment group, those who dismissed at t1 and those who did not dismiss at t1 have similar views on the merits of the case (36% and 34%, respectively). Nonetheless, the rejectors who did not dismiss at t1 reported a lower standard. This plausibly reflects a similar perception of the evidence, but a self-justificatory approach to the standard.

  26. 26.

    At t1, those who decided for (against) the plaintiff reported a confidence level of 3.99 (3.77). At t2, those who decided for (against) the plaintiff reported a confidence level of 3.67 (3.74). See, respectively, Tables 2 and 4.

  27. 27.

    The previous precedent also directed “that a complaint should not be dismissed… unless it appears beyond doubt that the plaintiff can prove no set of facts in support of his claim…” (Conley v. Gibson, 355 U.S. 41 [1957], pp. 45–46).

  28. 28.

    For instance, this description has not taken into account the behavior of defendants, and in particular repeat-defendants, who have to trigger dismissal motions under the current regime. Anecdotally, surveys suggest that defendants are not inclined to move to dismiss after Twombly (Hubbard 2016, p. 737).


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We thank Ilana Ritov, Dan Simon, Theresa Squatrito, Eyal Zamir, and participants in the tribute workshop in honor of Theodore Eisenberg, the Italian Society of Law and Economics annual conference, and the Conference on Empirical Legal Studies in Europe for useful discussions and comments. We thank Ofir Givaty, Daniel Fishelovich, and Sharon Salinas for excellent research assistance. This research project was supported by the Israeli Science Foundation (Grant No. 1251/15).

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Correspondence to Shay Lavie.

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Lavie, S., Ganor, T. & Feldman, Y. Adjusting legal standards. Eur J Law Econ 49, 33–53 (2020).

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  • Empirical legal studies
  • Legal thresholds
  • Coherence-shifts
  • Dismissal standards
  • Twombly

JEL Classification

  • K40
  • K41
  • D91
  • C91