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Manual for Complex Litigation - Surveys

§11.493 Sampling/Opinion Surveys

Statistical methods can often estimate, to specified levels of accuracy, the characteristics of a “population” or “universe” of events, transactions, attitudes, or opinions by observing those characteristics in a relatively small segment, or sample, of the population.

Acceptable sampling techniques, in lieu of discovery and presentation of voluminous data from the entire population, can save substantial time and expense, and in some cases provide the only practicable means to collect and present relevant data. In one case, for example, a statistical expert profiled the compensatory damage claims of the class members to assist the jury in fixing the amount of punitive damages.

The choice of appropriate sampling methods will depend on the objective. There is a difference between sampling to generate data about a population so the data will be verified or declared true and sampling, like polling, to measure opinions, attitudes, and actions by a population. In the case of the former, the reliability and validity of estimates about the population derived from sampling are critical.

The sampling methods used must conform to generally recognized statistical standards. Relevant factors include whether

- the population was properly chosen and defined;

- the sample chosen was representative of that population;

- the data gathered were accurately reported; and

- the data were analyzed in accordance with accepted statistical principles.

Laying the foundation for such evidence will ordinarily involve expert testimony and, along with disclosure of the underlying data and documentation, should be taken up by the court well in advance of trial. Even if the court finds deficiencies in the proponent’s showing, the court may receive the evidence subject to argument going to its weight and probative value.

By contrast, questioning a sample of individuals by opinion polls or surveys about such matters as their observations, actions, attitudes, beliefs, or motivations provides evidence of public perceptions. The four factors listed above are relevant to assessing the admissibility of a survey, but need to be applied in light of the particular purpose for which the survey is offered. In addition, in assessing the validity of a survey, the judge should take into account the following factors:

- whether the questions asked were clear and not leading;

- whether the survey was conducted by qualified persons following proper interview procedures; and

- whether the process was conducted so as to ensure objectivity (e.g., determine if the survey was conducted in anticipation of litigation and by persons connected with the parties or counsel or by persons aware of its purpose in the litigation).

Parties who propose to offer sampling or survey evidence may want to consider whether to disclose details of the proposed sampling or survey methods to the opposing parties before the work is done (including the specific questions that will be asked, the introductory statements or instructions that will be given, and other controls to be used in the interrogation process). Objections can then be raised promptly and corrective measures taken before the survey is completed. A meeting of the parties’ experts can expedite the resolution of problems affecting admissibility.

Parties sometimes object that an opinion survey, although conducted according to generally accepted statistical methods, involves impermissible hearsay. When the purpose of a survey is to show what people believe—but not the truth of what they believe—the results are not hearsay. In the rare situation where an opinion survey involves inadmissible hearsay, Federal Rule of Evidence 703 nevertheless allows experts to express opinions based on the results of the survey.

By Harper Litigation Consulting and Research
Trademark and Trade Dress Surveys, Marketing, Licensing, Advertising - Expert Witness
ABOUT THE AUTHOR: Harper Litigation Consulting and Research
Founded in 2005, Harper Litigation Consulting and Research has been trusted by hundreds of law firms. Ms. Rhonda Harper is a courtroom proven expert witness, having testified in virtually every circuit, along with AAA, JAMS, TTAB, and the PTO. As a former Fortune 100 chief marketing officer and an adjunct marketing professor, she has provided testimony in cases involving intellectual property infringement, misleading advertising, licensing, breach of contract and performance, unfair competition, consumer privacy, personal injury, and more. Ms. Harper has conducted or rebutted more than 200 intellectual property surveys.

Copyright Harper Litigation Consulting and Research

Disclaimer: While every effort has been made to ensure the accuracy of this publication, it is not intended to provide legal advice as individual situations will differ and should be discussed with an expert and/or lawyer.For specific technical or legal advice on the information provided and related topics, please contact the author.

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