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On the Meaning of the Preponderance Test in Judicial Regulation of Chemical Hazard

Page, Talbot (1984) On the Meaning of the Preponderance Test in Judicial Regulation of Chemical Hazard. Social Science Working Paper, 515. California Institute of Technology , Pasadena, CA. (Unpublished)

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As usually defined, the preponderance test is a standard of proof which directs the jury to accept the plaintiff's version of the disputed facts if they are more probably true than not. But what happens when the most important disputed "facts" are judgments about probability? This paper offers an interpretation of the preponderance test which can be applied to this situation. In the example of the paper, B is the benefit of a drug, C is the health cost if it is a teratogen, and p is the probability of teratogenicity. The contested "fact" is the magnitude of p, the probability of harm. In the interpretation considered by the paper, the jury finds in favor of the plaintiff if the jury decides that it is more likely than not that p is greater than B/C. This definition of the preponderance test does not quite minimize expected costs, and compared with expected cost minimization it is likely to be biased toward under-protection when the health costs are high compared with the benefits. But when the mean and median of the second order probability of p are the same, the definition coincides with expected cost minimization. It is also shown that under a criterion of expected cost minimization, contrary to Posner, judicial error costs are not in general the same and the number of erroneous judgments favoring undeserving plaintiffs is not likely to be the same as the number of erroneous judgments favoring undeserving defendants.

Item Type:Report or Paper (Working Paper)
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Additional Information:This research was supported by the National Science Foundation and the Mellon Foundation, The paper owes much to Jim Krier, who generously contributed much of the first two sections. Published as Page, Talbot. "On the meaning of the preponderance test in judicial regulation of chemical hazard." Law and Contemporary Problems 46.3 (1983): 267-283.
Group:Social Science Working Papers
Funding AgencyGrant Number
Andrew W. Mellon FoundationUNSPECIFIED
Subject Keywords:Minimization of cost, Plaintiffs, Defendants, Toxicity, Statutory interpretation, Financial liabilities, Economic costs, Court costs, Chemical hazards, Burden of proof standards
Series Name:Social Science Working Paper
Issue or Number:515
Record Number:CaltechAUTHORS:20170920-135918033
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:81629
Deposited By: Jacquelyn Bussone
Deposited On:20 Sep 2017 21:12
Last Modified:03 Oct 2019 18:45

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