Element of Proof - Causation

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1 Use of Fact and Expert Witnesses Burden of Proof Burden of proof (Latin: onus probandi) is the obligation to prove allegations which are presented Necessitas probandi incumbit ei qui agit ("the necessity of proof lies with he who complains. _ Burden of Production - Produce evidence supporting claims (prima facie case). Burden shifts between parties over the course of the hearing or trial. Burden of Persuasion - obligation that remains on a single party for the duration of the claim. Once the burden has been entirely discharged to the satisfaction of the trier of fact, the party carrying the burden will succeed For example, the presumption of innocence places a legal burden upon the prosecution to prove all elements of the offense (generally beyond a reasonable doubt) and to disprove all the defenses except for affirmative defenses 2 B of Proof in Practice Defendant (D) is alleged to have violated the CWA NPDES Permit Burden of Proof: Government Burden of Production: P has to produce evidence proving D violated its permit Failure to meet the burden: the issue will be decided as a matter of law (the judge makes the decision), in this case, D is not liable Burden of persuasion: If at the close of evidence, the jury cannot decide if P has established with relevant level of certainty that D had violated its permit, the jury must find D not liable of violation Standard of Proof The "standard of proof" is the amount of proof required in a legal action to discharge the burden of proof, that is to convince the court that a given proposition is true. Preponderance of evidence - (lowest level of proof, used mainly in civil trials) Beyond a reasonable doubt - (highest level of proof, used mainly in criminal trials) Clear and convincing evidence - (which is the medium level of proof, used, for example, in cases in which the state seeks to terminate parental rights). 3 4 Element of Proof - Causation Plaintiffs were required to identify the sources of the pollutants that they alleged caused the underlying injuries of which they suffered In order to meet the burden of establishing causation, the plaintiff will use Fact Witness Testimony Physical evidence Expert Witness Testimony Witness Evidence is introduced into the record at trial via either witnesses or stipulations Two Types of Witnesses Fact witness testify from first-hand knowledge, limited testimony re opinion Expert Witness Can testify as to opinion based upon his or her training, education or experience Direct vs. Cross Examination 6 1

2 Fact Witness Testimony Fact witnesses generally testify based upon their first hand knowledge (things that they have observed or heard), only allowed to offer lay opinions Direct Examination testimony elicited from the person who called the witness to the stand Must ask open-ended, non-leading questions Can introduce documents or other pieces of physical evidence into the record of the case via a witness Witness helps to lie the foundation for the piece of evidence It is what it purports to be/ It is the original or a full and accurate copy/ It is reliable Video of Fact Witness Testimony A Few Good Men Chapter 18 (Direct/Cross of Fact Witness) Chapter 15 (Stipulation as to adverse testimony) My Cousin Vinny Chapter 10 (Fact witnesses at probable cause hearing) Chapter 17/18 (Cross examination of fact witnesses at trial) 7 8 Expert Witness A witness who, based upon his training, experience or knowledge that is not possessed by the normal person, is able to provide the jury with an opinion that will assist the jury with its deliberations Opinion must be based on a reliable methodology Consider the specific facts of a case Qualified as expert - court must accept person Witness will testify as to the facts that he or she has taken into consideration re offering opinion Cross-Examination testimony elicited by a person who did not call the witness to the stand Can ask leading questions Federal Rule of Evidence 702 Rule 702. Testimony by Expert Witnesses A witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if: (a) the expert s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue; (b) the testimony is based on sufficient facts or data; (c) the testimony is the product of reliable principles and methods; and (d) the expert has reliably applied the principles and methods to the facts of the case. 9 Qualification of an Expert Basis of Expert Qualification - Knowledge, skill, experience, training, or education Voir Dire of Qualifications Offering party and other party ask questions of expert to address his or her qualifications Offered as an expert in a particular field Accepted or rejected by the Court Video of Expert Testimony A Few Good Men Chapter 16 (Voir dire of expert witness) My Cousin Vinny Chapter 19 (Testimony of government expert witness) Chapter 21 (Voir Dire of expert witness) My Cousin Vinny 12 2

3 Need for Expert Testimony The expert s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue The matter on which the expert witness will be offering testimony cannot be a matter that a lay person/member of the jury can understand and resolve based on his or her knowledge, etc. Need for expert help ex., scientific, engineering, financial, technical, medical issues that require special training or experience Underlying Factual Basis The testimony is based on sufficient facts or data In order to render an expert opinion, the expert witness must be sufficiently familiar with and must have relied upon the factual circumstances of a matter to form his or her expert opinion As part of the testimony offering the opinion, the expert witness will explain the facts that he or she considered for purposes of rendering his or her opinion My Cousin Vinny Methodology The testimony is the product of reliable principles and methods; and the expert has reliably applied the principles and methods to the facts of the case. Reliability of the methodology used by the expert in order to come to his or her conclusions How to determine if a method is reliable? How can opinion or junk science be kept out of the courts? Frye Test In Frye v. U.S. (1923) expert testimony was admissible only if based upon techniques and procedure generally accepted in the scientific community. Experts were challenged during voir dire: this is a specific step in the pre-trial procedure to question experts (and jurors) about their qualifications and biases. While courts will go a long way in admitting expert testimony deduced from well-recognized principles or discovery, the thing from which the deduction is made must be sufficiently established to have gained general acceptance in the particular field in which it belongs. The Frye test was used for decades because: Those most qualified to assess the scientific method used will have a determinative voice. Consensus in a scientific community would promote uniformity of decisions. Frye s conservative nature protects all parties: it created a mechanism for evaluating reliability in a consistent manner, since jurors tend to give undue weight to scientific evidence when presented by experts with impressive credentials. Frye has limits Frye Test also had limits in that it did not recognize advancements in certain fields and that cutting edge new processes/ideas may be reliable even if they had not been generally accepted yet Also, sometimes it was difficult to find experts to testify that a method was generally accepted given the underlying claims of a case 3

4 Daubert v. Merrell Dow Pharmaceuticals (1993) Daubert v. Merrell Dow Pharmaceuticals (1993) The 1993 case of Daubert v. Merrell Dow Pharmaceutical, Inc., the U.S. Supreme Court asserted that the Frye standard is not an absolute prerequisite to the admissibility of scientific evidence. Plaintiffs offered testimony from 8 experts alleging that Bendectin (an anti-nausea drug taken during pregnancy) was teratogenic (caused birth defects). The Supreme Court excluded the experts from testifying (ruled in favour of the defendants) and took this opportunity to enunciate a new standard for admissibility of expert evidence. The Supreme Court upon reviewing Daubert held that the Federal Rules of Evidence 702 (1975) and not Frye were the criteria by which scientific evidence should be measured. The Federal Rules of Evidence, up until Daubert, did not hold the precedence that Frye had and was not used often in trial court proceedings. The Daubert opinion was intended to liberalize the admission of evidence and allowed the judge to play the role of the gatekeeper. Daubert v. Merrell Dow Pharmaceuticals (1993) Trial courts should act as gatekeepers and exclude expert testimony that is unreliable. These rules are in place to help the trier of fact understand the evidence and determine its relevance. To assist trial court judges the Supreme Court listed factors to help determine the admissibility of scientific evidence. While benefiting the newer quantitative fields of forensic science, these factors, placed greater admissibility pressure on the comparative sciences (fingerprints, hair and fiber). The Daubert Criteria In Daubert, the Supreme Court offered some guidelines as to how a judge can gauge scientific evidence: Whether the scientific technique or theory has been tested. Whether the technique has been subject to peer review and publication. The technique s potential rate of error. Existence and maintenance of standards controlling the technique s operation. Whether the scientific theory or method has attracted widespread acceptance within a relevant scientific community. Kumho Tires Co. v.carmichael (1999) Kumho plainly invite[s] a reexamination even of generally accepted venerable, technical fields. United States v. Hines (D. Mass. 1999) Handwriting comparison Fingerprint comparison Hair comparison Firearms identification ( ballistics ) George F. Pinder, Ph.D Expert witness on groundwater hydrology offered by the plaintiffs to establish: With regard to both Grace and Beatrice, TCE and other solvents from these companies properties had migrated to Wells G and H; and The chemicals had reached Wells G and H before the leukemias and other illness began occuring Pinder was chairman of the civil engineering department of Princeton University and developed the first computer model of groundwater flow 4

5 George F. Pinder, Ph.D Education Ph.D., University of Illinois, June 1968 B.Sc. (Honors), University of Western Ontario, June 1965 Professional 1989 to present Professor:, College of Engineering and Mathematics, University of Vermont, Burlington, Vermont 1972 to June 1989 Professor/Dean/Chairman, Department of Civil Engineering, Princeton University, Princeton, New Jersey Dec Sept Research Hydrologist, U.S. Geological Survey, Water Resources Division, Atlantic Coast Region, Arlington, Virginia June 1968-Dec Nova Scotia Department of Mines, Nova Scotia, Canada George F. Pinder, Ph.D Professional Societies Society of Sigma Xi, Phi Kappa Phi, American Society of Civil Engineers, Society of Petroleum Engineers of AIME, American Geophysical Union, Society for Industrial and Applied Mathematics, American Institute of Hydrology Professional Activities Editorial Boards (1) Applied Mathematics Modelling (2) Applied Numerical Mathematics (3) Communications in Applied Analysis (4) International Journal of Computational and Numerical Analysis and Applications (5) International Journal of Pure and Applied Mathematics Editor-in-Chief (1) Numerical Methods for Partial Di erential Equations Founding Editor (1) Advances in Water Resources (2) Numerical Methods for Partial Di erential Equations Professional Boards Board of Advisors, Wessex Institute of Technology, Ashurst, England External Advisory Committee, Water: Systems, Science and Society, Tufts Univer Pinder Introduction/Qualification GEORGE PINDER, SWORN DIRECT EXAMINATION BY MR. SCHLICHTMANN Q Would you please state your name for the record? A George Pinder. Q Dr. Pinder, what is your profession? A I'm a Professor at a university. Q Which university is that? A Princeton. Q And do you live in Princeton? Q And what is your position at Princeton University? A I'm Chairman of the Department of Civil Engineering. Q And could you briefly review for the jury your educational background? A I have a Bachelor of Science in geology from the University of Western Ontario, from Canada, and I have a Ph.D. from the Department of Geology at the University of Illinois. THE COURT: University of what? THE WITNESS: Illinois. A With a minor in civil engineering and statistics. Pinder Introduction/Qualification Q: And did you -- could you review your professional experience since attaining your educational degrees? A Upon receiving my Bachelor's degree, I worked for several years in the summertime for the Nova Scotia Department of Mine as a field hydrologist. That continued into the time when I began to work on my doctorate. Subsequent to my doctorate I worked for the U.S. Geological Survey as a research hydrologist in Washington, D.C. In 1972 I left that position and came to Princeton as an Associate Professor of civil engineering and geological engineering. Note: Cheesman had tried to hire Pinder to be his expert witness, but Schlictmann had gotten to Pinder first (p. 326) Q Is it customary in your profession to make use of this type of information? A. Yes, sir. Q And is it customary in your profession to receive this type of information from consultants like Weston Geophysical? A. Yes, sir, that is the typical way it is done. Q In using this information, did you, in fact, make determinations of the groundwater flow in the East Woburn aquifer? A. Yes, sir, I did. Q What are the methods that you used to determine the groundwater flow in the East Woburn aquifer? A. Well, the method that I used was basically the same concept that I've been describing to you today, the idea of taking well locations, connecting them with triangles, and then for each triangle determining the direction of groundwater flow for that particular triangle A: What I have done here is located those wells where we had water level elevations prior to the initiation of the pump tests at the Woburn site. This represents the undisturbed picture of the groundwater flow at that time.. So you can see that, for example, you just look at the Grace site, we have very large arrows, very wide arrows: The thicker the arrow, the steeper the grading, the steeper the water table. So you can see clearly there are large arrows up in the Grace site indicating steep gradient moving basically to the west and as they get to the neighborhood of the river they tend to move to the south in the direction of the river: 5

6 The gradients tend to get shallower. That is these are very thin arrows in this area, because in the area along the river the water table is fairly flat, but the material is very permeable. In other words, it will allow water to move through it very fast. So the fact that these arrows are small does not mean there is not very much water flowing through, it just means it does not take very much energy to push it along. The same is true with the low gradients on the Beatrice property basically moving some areas toward the river and some areas to the south, and what you see here, these arrows are probably in response to the pumping of the Riley well down this section. Mr. Riley has his own well. So this is the Beatrice side, and you can see the general flow of the groundwater on the Beatrice side, and you can see the general direction of flow of the groundwater on the eastern side, and that is associated with Grace. Q: And, Dr. Pinder, you explained the method that you used in determining the groundwater flow for the East Woburn aquifer. Are there other methods that can be used in your profession to determine groundwater flow other than what you just demonstrated? A. This is a direct method. There is an indirect method where you use a computational method of known parameters and then calculate based on those parameters what the direction of flow has to be in the aquifer system: That is more abstract. It is well-accepted methodology. It then does not rely on the same data that these arrows rely upon. In the sense, it is an independent check of your conception of the system. Q. Did you undertake that analysis as well? A. Yes. We also did that: Q Tell the jury, please, Dr. Pinder, how you used the information that you have described in making this independent calculation about groundwater flow in East Woburn. A. What we do is take all the information that we have regarding the physical system as we understand it, and then we use a computational method to take that information and try and predict what the water levels will be in the system, given all the other information that is put in, and that generates a set of gradients very much, that look very much like the kinds of gradients that I have shown you before, in the sense that they are -- The arrows are the same shape and things like that. And that basically constitutes a separate and distinct calculation not depending directly on water levels themselves, but rather creating water levels computational. based on everything else we know about the physical system. Q. And is this a methodology which is used in your profession? A. It is very commonly used, yes. Q. And in this case did you, in fact, form opinions based on the calculations that you have described about groundwater flow in East Woburn? A. Yes. Q What is that opinion? A: It is my opinion that contamination from Beatrice would reach the well field under pumping conditions in less than a year's time. DIRECT EXAMINATION BY MR. SCHLICHTMANN, CONTINUED Q Dr. Pinder, yesterday I asked you questions about transport times for contaminants at the Grace site, do you recall that? Q Do you have an opinion as to how long it would take for trichloroethylene introduced at the Grace site to travel to the well field of G and H? Q What is that opinion? That it would be no more than three years. Q Do you have an opinion as to the transport time for tetrachloroethylene introduced at the Grace site to travel to the well field of G and H? A Based on retardation, it should be approximately four times longer. THE COURT: Four times longer than the trichloroethylene? THE WITNESS: Yes, sir. THE COURT: So it would take 12 years? THE WITNESS: Yes, sir. Approximately Pinder s Mistake With regard to the transit times, Pinder forgot to factor in the porosity of soil Pinder believed that it was a minor error in that the solvents reached Wells G and H long before the leukemias began occurring. Schlichtmann the following day has Pinder correct his mistake on the stand 6

7 Pinder Cross Correcting His Mistake Q Now, Dr. Pinder, yesterday I asked you questions about the travel times of chemicals; do you recall that? A Yes, sir: (Witness refers to document.) Q Now, you gave us some figures for different chemicals. Could you explain to the jury briefly the type of formula you were using or what you factored into that opinion? A Yes, I would be very pleased to do that. Yesterday I was asked by the attorney and also by the Judge to give travel times for contaminants other than TCE. You may recall that I gave, for example, a travel time for TCE of three years from Grace. I then did a mental calculation for the remaining chemicals as to how long they should take. In so doing, I left off a porosity term in my head that should have been in that calculation. So, I would be very pleased to try and correct that mistake. Pinder Cross Correcting His Mistake Q Does it affect the travel time in some way? A It affects the travel times not catastrophically, but I think significantly, at least from my point of view. Q Would you like to make those corrections? THE WITNESS: Would that be all right, your Honor? THE COURT: Certainly.. Q The corrections, then, is it fair to say, you have reduced the travel times for tetrachloroethylene for a few years -- or by a few months, in the case of Beatrice? Q And that you increased the travel times for transdichloroethylene for Grace from a few months to a year or more? Q And trans-dichloroethylene from the Beatrice site from a few weeks to a month? A Yes, sir. Pinder Cross Correcting His Mistake Q And could you just explain to the jury what caused you to make that recorrection? A Well, I just was contemplating my testimony and it suddenly occurred to me that I had made a mistake, and so I wanted to correct it: Q No, what was the mistake that you actually made? A I actually left off a constant when I was doing the multiplication in my head, that affected everything: Q That is a constant A It is the porosity of the soil which was.2, which affected, somewhat, everything. Facher s Cross P.328-9: Facher to Pinder - Are you telling this jury that you came in here yesterday, as a Ph.D. and the chairman of a department, and made a little mistake in an opinion you ve been preparing for the last year and a half? Facher again You re telling us, as a professor of geology, that your forgot to take into account porosity? Didn t you lecture in front of this jury for an hour about making these calculations Today is true and yesterday was not? That is what you want this jury to believe? Use of depositions to Cross Prior to taking the witness stand, as part of discovery a prospective witness usually takes part in a deposition and answers questions asked by attorneys to a case, under oath. The testimony is then transcribed. As part of testimony at a trial, a witness credibility can be impeached if his or her testimony differs from the deposition testimony Pinder s wife advsed him to read your deposition so you won t contradict yourself. P. 329 Pinder failed to heed this advice Deposition vs. Witness Stand Facher notes that in Pinder s deposition he testified that contaminants had reached the well field from Beatrice in 18 months, but on witness stand Pinder shortened it to 12 months p. 329 Pinder was wary of Facher. He looked for a trap in every question that Facher asked. To avoid being trapped, he refused to answer even the simplest of questions in a simple way. p

8 The Drobinski Issue Facher asked Pinder about the work of another expert that the plaintiffs were using John Drobinski a geologist (who based on his sampling of soil would testify that the Beatric property adjacent (15 acres) to the tannery had been contaminated for at least 25 years. Pinder testified I m not really familiar with what he did in detail. I think in spirit he went back and found some additional things. Facher asked: You didn t even know who Mr. Drobinski was back in December of 1985, did you? Pinder: Oh yes, I knew who he was. We had talked together many times. Deposition Facher asked Pinder if Pinder had worked directly with any Weston geologist. Pinder who said yes could not name anyone specifically, however. Loss of Credibility with the Judge P. 331 Judge to Schlichtmann I m beginning to think that this fellow has either got a very loose grasp of the language, or he will say anything that comes into his head. Attacking Facher s Defense Facher argued through his experts that the pumping action of the wells would draw water directly out of the river satisfying the well s demand while at the same time blocking the flow of contaminated ground water from Beatrice. Pinder reasoned that a thick layer of peat formed the riverbed and acted as a nearly impermeable lining or a barrier to the ground water. (p. 332) Problem When wells were pumping the level of the river seemed to drop. Pinder s explanation Under normal conditions, groundwater in aquifer would discharge into the river, increasing its volume. But when Wells G and H were pumping, they would draw from the aquifer and it could not discharge into the river, thereby causing the river level to fall. River not losing water, just not gaining it from aquifer. P. 334 Attacking Facher s Defense Problem US Geological Survey data contradicted Pinder s claim. Survey had measured the Aberjona s flow at a bridge crossing north of the Wells and at a spot 1000 yards downstream from the Wells. If river was not really losing water just not gaining any from the aquifer with the Wells pumping, then one would expect the flow at the upstream measuring device to equal the flow at the downstream device. But the Survey found the opposite. The two measurements were not equal. They showed that the river s flow did indeed decline by about 600 gallons per minute Pinder Attacked on Cross After testifying to this theory Pinder is attacked on cross. P Later EPA confirms Pinder s theory. P. 339 Cross examinatino is beyond any doubt the greatest legal engine ever invented for the discovery of the truth. A lawyer can do anything with a crossexamination... He may, it is true, do more than he ought to do. He may make the truth appear like falsehood. - John Wigmore 8