Chapter 6:
Pretrial and Trial Practice
VI. Expert Testimony
Daubert v. Merrill Dow Pharmaceuticals began a revolution in federal expert witness practice by greatly expanding the power of federal courts to exclude or limit expert testimony./335/ Before Daubert, trial judges largely confined admissibility determinations to qualifications. The proponent bore the burden to demonstrate that the expert was qualified through education, knowledge, experience, skill, or training to render an expert opinion. Daubert expanded the “gatekeeping function.”/336/ It held that, in addition to determining whether an expert is qualified to testify on the matters she proposes to address, the court must also determine whether the expert’s methodology is sufficiently reliable to support the opinions she proposes to offer. The court must further decide whether the expert’s proposed testimony will, through the application of scientific, technical, or specialized expertise, assist the trier of fact in understanding the evidence or determining a fact in issue./337/ Daubert arose from a dispute over scientific expert testimony and Kumho Tire Co. v. Carmichael subsequently expanded its holding to the admissibility of all non-scientific expert testimony./338/ In 2000, Federal Rule of Evidence 702 was revised to essentially codify Daubert; it states:
If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if (1) the testimony is based upon sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.
Unless the trial judge is satisfied that the expert’s proposed testimony passes muster under each inquiry, she will exclude the testimony, subject to appellate review for abuse of discretion./339/
VI.A. Qualifications
Qualification as an expert does not require a scientific background. Expert status may be based on extensive experience, knowledge, skill, or on-the-job training, even in the absence of formal education./340/ Disputes over the strength of qualifications and credentials ordinarily go to the weight to be accorded to expert testimony, and not to its admissibility./341/ As Daubert noted, “[v]igorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence.”/342/
VI.B. Reliable Principles and Methods
Daubert requires an inquiry into reliability “to make certain that an expert, whether basing testimony upon professional studies or personal experience, employs in the courtroom the same level of intellectual rigor that characterizes the practice of an expert in the relevant field.”/343/ Accordingly, Daubert directed that trial courts consider as part of the reliability inquiry for scientific expertise: (1) whether the expert's theory can and has been tested;/344/ (2) whether the theory has been subjected to peer review and publication;/345/ (3) the known or potential rate of error of the particular scientific technique,/346/ and (4) whether the technique is generally accepted in the scientific community./347/ Kumho Tire applied the same criteria to assess the reliability of experience with respect to non-scientific expert testimony./348/ The specified factors are guideposts; there is no requirement that a district court consider each of them, or that an expert’s testimony must satisfy each of the listed factors./349/
Daubert noted that its required reliability inquiry should be “a flexible one.”/350/ Although Daubert emphasized that “[t]he focus, of course, must be solely on principles and methodology, not on the conclusions that they generate,”/351/ General Electric Company v. Joiner insisted that “conclusions and methodology are not entirely distinct,”/352/ thereby expanding the trial court’s authority to exclude proposed testimony as unreliable. Nonetheless, an application of the Daubert-Kumho test to an expert’s economic analysis would generally not require validating the conclusion, but would require determining whether an accepted methodology was used in conducting the analysis./353/
VI.C. The Fit Between Methods and Conclusions
Joiner expanded the reliability inquiry to include an assessment of the fit between each of the expert’s specific opinions and the data, principles, and methods from which it is purportedly derived. The Court reasoned that even when an expert uses reliable methods and data, “[a] court may conclude that there is simply too great an analytical gap between the data and the opinion proffered” and that “nothing in either Daubert or the Federal Rules of Evidence requires a district court to admit opinion evidence that is connected to existing data only by the ipse dixit of the expert.”/354/
In the wake of Joiner, several recent Section 1983 claims dependent on expert testimony have foundered for lack of sufficient fit between the expert’s opinions and underlying data./355/ However, when fit can be shown, the court should admit the expert’s opinion, leaving for the jury the question of whether to credit the testimony./356/ The Advisory Committee Notes to amended Rule 702 caution that “’the trial court’s role as gatekeeper is not intended to serve as a replacement for the adversary system.’”/357/
VI.D. Reliance upon Other Experts
Experts routinely rely on the work of others; that reliance is not objectionable as hearsay./358/ An expert appropriately may rely upon reports of others to formulate his opinion, and such reliance is often an indicia of reliability./359/ Similarly, consultation with other experts can be a reliable and appropriate methodology under Daubert./360/
VI.E. Will Expert Testimony Assist the Trier of Fact?
Federal Rule of Evidence 702 requires that admissible expert testimony assist the trier of fact. Expert testimony only assists the trier of fact when it addresses matters beyond the ready understanding of the ordinary juror. It does not do so when it only addresses matters counsel can present through closing argument./361/ Similarly, expert testimony will not assist the trier of fact by explaining the governing law; that is the responsibility of the court./362/ Moreover, Daubert expanded trial court’s authority to exclude evidence under Federal Rule of Evidence 403:
Finally, Rule 403 permits the exclusion of relevant evidence “if its probative value is substantially outweighed by the danger of unfair prejudice, confusion of the issues, or misleading the jury . . . ”Judge Weinstein has explained: “Expert evidence can be both powerful and quite misleading because of the difficulty in evaluating it. Because of this risk, the judge in weighing possible prejudice against probative force under Rule 403 of the present rules exercises more control over experts than over lay witnesses.”/363/
VI.F. Expert Testimony in Practice
Expert testimony can be crucial to proving causation and it is particularly likely to trigger reliability and fit objections./364/ To qualify as reliable, causation testimony need not negate every alternative hypothesis; “‘[i]n order to be admissible on the issue of causation, an expert’s testimony need not eliminate all other possible causes of the injury.’”/365/ Thus, the Seventh Circuit held that a district court properly admitted expert testimony by a psychology professor in support of the claim by a wrongly convicted, later exonerated, plaintiff that police officers who deliberately showed photos of the plaintiff to eyewitnesses just before a lineup caused them to misidentify him as the killer. Experiments performed by the expert were found to be reliable by the standards of his field./366/
Expert testimony from police practices experts often plays a crucial role in establishing excessive force claims. Recent Sixth Circuit cases are instructive. Champion v. Outlook Nashville, Inc., held admissible expert testimony from a police procedure expert who specialized in creating use of force policies. The testimony described the force continuum, and that concluded that the particular use of force violated nationally recognized police standards./367/ Champion distinguished an earlier circuit case excluding expert testimony by a police practices expert,/368/ noting that the tightly focused character of the expert’s testimony in Champion was crucial to its admissibility./369/
Although Champion approved the use of expert testimony against individual officers to establish that a particular use of force was excessive, Thomas v. City of Chattanooga foreclosed its use against a city to support a claim that one incident and a number of civilian complaints of excessive force showed an unwritten city policy or custom of condoning excessive force./370/ Absent a determination of whether the complaints were “serious or frivolous” or a quantitative analysis of comparative evidence from other similar cities, the expert’s proposed testimony was unsupported by any reliable methodology./371/ Similarly, his conclusion that the inadequacy of the subsequent investigation of the incident was insufficient to show a municipal policy because the expert “did not reach beyond the facts of this case to show any possibility of a pattern.”/372/
VI.G. Determining Admissibility of Expert Testimony
The burden of establishing the admissibility of expert testimony rests with its proponent./373/ An opposing party can challenge the admissibility of all or part of proposed expert testimony before trial through a motion in limine or through voir dire when the expert is tendered at trial. The volume of reported cases suggests that many if not most objections now arise pretrial in motions in limine. Accordingly, the proponent should anticipate and prepare from the outset to overcome a motion in limine, beginning with the preparation of the expert’s report.
Rule 26(a)(2)(B) of the Federal Rules of Civil Procedure requires parties to disclose the names of their retained trial experts before trial and to give the opposing party a written report, prepared and signed by the expert witness that must contain “a complete statement of all opinions to be expressed by the expert and the basis and reasons therefore.” Parties must also provide “the data or other information considered by the witness in forming the opinions,” exhibits, the expert’s qualifications (including publications) and compensation, and a listing of expert testimony during the preceding four years. The report should be sufficiently comprehensive to establish admissibility under all of the Rule 702 criteria. A trial court has discretion to grant a motion in limine without first conducting an evidentiary hearing if the expert’s report fails to establish one of the elements required for admissibility./374/
In limine motions generally follow an expert’s deposition. Although courts frequently hold evidentiary hearings to resolve in limine motions, often referred to as Daubert hearings, the determination of whether to conduct a Daubert hearing is committed to the discretion of the trial court, and a trial court can grant or exclude an expert’s testimony without first conducting a Daubert hearing./375/ Like all evidentiary objections, Daubert objections to the admissibility of an expert’s testimony can be waived by failing to timely raise them in the trial court./376/
VI.H. Examination of Experts at Trial
Successful examination of experts on both direct and cross requires extensive preparation. You must try to learn as much as the expert knows in the narrow area of examination. Your expert can help you design her testimony after you explain the needs of your case. When preparing your expert to testify before trial, have her respond verbally to the key questions that you intend to ask at trial in order to be certain that the manner in which she answers is clear, understandable, and legally acceptable. Remember that professors are usually good teachers and familiar with effective teaching techniques. Many experts, however, especially those whose expertise is in highly technical fields and who have little or no testifying experience, are unaccustomed to explaining complex matters to lay people. Their explanations can be somewhat more sophisticated in a bench trial. Nevertheless, the explanations must be expressed in a way that makes them interesting and understandable to the judge. In addition, experts are not likely to self-edit. Prepare them carefully to avoid extraneous information or opinions. A practice session with role playing can be invaluable, particularly with a novice expert. Review with your expert the questions you anticipate on cross-examination. Create or review with the expert the visual aids that might help the jury understand the testimony or stay interested in it. Remind the expert to maintain poise and not bicker with a difficult questioner.
In working with your expert and in preparing your case for trial, consider the foundation on which you will rely as the basis for her opinion. Expert opinions may be based on firsthand knowledge, evidence admitted at the hearing, and other facts or data, if “of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject.”/377/ Thus an expert witness may rely on hearsay or unauthenticated evidence./378/ Whether the inadmissible evidence is disclosed to the jury, however, is within the judge’s discretion, Federal Rule of Evidence 703 states: “Facts or data that are otherwise inadmissible shall not be disclosed to the jury by the proponent of the opinion or inference unless the court determines that their probative value in assisting the jury to evaluate the expert’s opinion substantially outweighs their prejudicial effect.”/379/
The extent to which the opinion is based on inadmissible evidence may also influence whether the court permits the expert to give her opinion before disclosing the basis for it./380/ Experts are not barred from expressing opinions on the “ultimate issue to be decided by the trier of fact.”/381/ Although experts are entitled to base their opinions on facts perceived by or made known to them, testifying experts may be excluded from the courtroom during the testimony of other witnesses under Rule 615 unless their presence is “essential.”/382/ Generally, if the expert has no firsthand knowledge of the facts, she is permitted to remain in the courtroom./383/ If the court appoints its own experts, you are entitled to depose and cross-examine them./384/
Cross-examination of experts requires the same type of preparation as direct. You must have thorough familiarity with the subject matter and relevant literature, especially anything the witness has written. Review previous testimony and reports by the expert or other experts in the case, and keep accessible any materials you will use for the examination. Statements in learned treatises recognized as such by the expert are a particularly potent source of cross-examination as they are admissible despite their hearsay status./385/
335. Daubert v. Merrill Dow Pharm., 509 U.S. 579 (1993).
336. Daubert, 509 U.S. at 589 n.7.
337. Peter Nordberg, an attorney with Berger & Montague in Philadelphia, maintains a very useful website and blog on Daubert and the many practice issues it generates: “Daubert on the Web,” www.daubertontheweb.com; the blog is BLOG 702, http://daubertontheweb.com/blog702.html.
338. Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999).
339. Gen. Elec. Co. v. Joiner, 522 U.S. 136 (1997).
340. See, e.g., Quiet Tech. DC-8, Inc. v. Hurel-Dubois UK Ltd., 326 F.3d 1333, 1343 (11th Cir. 2003) (expert who had worked in field for nearly twenty years; had worked with experts in field; and had extensive on-the-job training was qualified); see also Smith v. Ford Motor Co., 215 F.3d 713, 718 (7th Cir. 2000) (“court should consider a proposed expert’s full range of practical experience as well as academic or technical training when determining whether that expert is qualified to render an opinion in a given area”).
341. See Jahn v. Equine Servs. PSC, 233 F.3d 382, 393 n. 8 (6th Cir. 2000) (citing McCullock v. H.B. Fuller Co., 61 F.3d 1038, 1045 (2d Cir. 1995)).
342. Daubert, 509 U.S. at 596.
343. Kumho Tire Co, 526 U.S. at 152.
344. Daubert, 509 U.S. at 593.
348. Kumho Tire, 526 U.S. at 152.
349. “Using the Daubert factors as a point of departure, the district court is free to fashion an approach more precisely tailored to an evaluation of the particular evidentiary submission before it.” U.S. v. Conn, 297 F.3d 548, 556 (7th Cir. 2002). See also Hudgens v. Bell Helicopters, 328 F.3d 1329 (11th Cir. 2003); Maiz v. Virani, 253 F.3d 641, 665 (11th Cir. 2001); Ancho v. Pentek Corp., 157 F.3d 512, 513 (7th Cir. 1998).
350. Daubert, 509 U.S. at 594.
352. Gen. Elec. Co., 522 U.S. at 146.
353. See, e.g., United States v. Diaz, 300 F.3d 66 (1st Cir. 2002); Atlantic Richfield v. Farm Credit Bank of Wichita, 226 F.3d 1138, 1166 (10th Cir. 2000); Blue Dane Simmental Corp. v. American Simmental Assoc’n, 178 F.3d 1035 (8th Cir. 1999); Figueroa v. Boston Scientific Corp., 254 F. Supp. 2d 361 (S.D.N.Y. 2003).
355. See, e.g., Nimely v. City of N.Y., 414 F.3d 381, 399 (2d Cir. 2005) (abuse of discretion to admit expert testimony of “misperception hypothesis” as explanation for variance between police officer perception and physical evidence in excessive force wrongful shooting claim); Burleson v. Tex. Dep’t of Criminal Justice, 393 F.3d 577 (5th Cir. 2004) (expert witness properly excluded in Eighth Amendment claim that defendants exposed plaintiffs to hazardous conditions as prison welder causing him to develop radiation induced cancer; no reliable methodology supported expert’s claim of harmful exposure level); McDowell v. Brown, 392 F.3d 1283 (11th Cir. 2004) (plaintiff’s expert witness properly excluded in claim by inmate that four hour delay in treating spinal epidural abscess caused or worsened resulting paralysis since studies only explored effects of 48 hour or longer delays; expert’s causation conclusion was therefore unreliable assertion). See also Fitzgerald v. Corr. Corp. of America, 403 F.3d 1134 (10th Cir. 2005) (holding inadmissible affidavit submitted by defense expert physician in support of summary judgment attesting to quality care offered by defendant physician; affidavit offered no factual foundation for its conclusion). But see United States v. Brown, 415 F.3d 1257 (11th Cir. 2005), cert. denied, 126 S. Ct. 1570 (2006) (district court did not abuse discretion in admitting expert testimony that the chemical structure of 1,4-butanediol is “substantially similar” to the chemical structure of GHB so as to bring the chemical compound within the definition of “controlled substance analogue” under 21 U.S.C. § 802(32)(A) even though experts “provided no additional methodology or basis for their opinions, and they cited no studies or other objective data” and one conceded on cross that “his determinations about whether chemical compounds are substantially similar is a “gut level thing” or based on “intuition,” from his thirty years as chemist. (citations for quotes scattered within opinion). Brown may reflect an unwritten and unacknowledged practice of easing Daubert requirements for government experts in criminal prosecutions.
356. “The soundness of the factual underpinnings of the expert’s analysis and the correctness of the expert’s conclusions based on that analysis are factual matters to be determined by the trier of fact.” Smith v. Ford Motor Co., 215 F.3d 713, 717 (7th Cir. 2000). The proponent of the expert testimony need not demonstrate that the testimony is correct – only that the expert is qualified, and that his testimony is based on reliable methodology. “[I]t is not the role of the district court to make ultimate conclusions as to the persuasiveness of the proffered evidence.” Quiet Technology DC-8, 326 F.3d at 1341. “[A] district court’s gatekeeper role under Daubert ‘is not intended to supplant the adversary system or the role of the jury.’” Id. (quoting Maiz v. Virani, 253 F.3d 641, 666 (11th Cir. 2001) and Allison v. McGhan, 184 F.3d 1300, 1301 (11th Cir. 1999)). See also ID Security Sys. Can., Inc. v. Checkpoint, 249 F. Supp.2d 622, 692 (E.D. Pa. 2003) (“emphasis in Rule 702 on ‘sufficient facts or data’ is not intended to authorize a trial court to exclude an expert's testimony on the ground that the court believes one version of the facts and not the other”), quoting advisory notes to Federal Rule of Evidence 702.
357. Fed. R. Evid. 702, advisory committee notes (quoting United States v. 14.38 Acres of Land Situated in Leflore County, Miss., 80 F.3d 1074, 1078 (5th Cir. 1996)).
358. An expert witness may rely upon hearsay information if that information is “of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject.” Fed. R. Evid. 703. See U.S. v. Mulder, 273 F.3d 91, 102 (2d Cir. 2001) (“[E]xpert witnesses can testify to opinions based on hearsay or other inadmissible evidence if experts in the field reasonably rely on such evidence in forming their opinions”); Rondout Valley Cent. Sch. Dist. v. Coneco Corp., 321 F. Supp.2d 469, 479 (N.D.N.Y. 2004) (facts on which expert relies upon need not be admissible in evidence for his opinion to be admitted; expert economist may rely upon “data that he did not personally collect”).
359. Walker v. Soo Line R.R. Co., 208 F.3d 581, 588 (7th Cir. 2000) (“Indeed, courts frequently have pointed to an expert’s reliance on the reports of others as an indication that their testimony is reliable”).
360. In re James Williams Assoc., 965 F.2d 160, 170 (7th Cir. 1992).
361. United States v. Frazier, 387 F.3d 1244, 1262 (11th Cir. 2004) (en banc), cert denied, 125 S. Ct. 2516 (2005) (citing 4 Weinstein's Federal Evidence § 702.03[2] [a] (2d ed. 1998)).
362. “Each courtroom comes equipped with a “legal expert,” called a judge, and it is his or her province alone to instruct the jury on the relevant legal standards.” Burkhart v. Washington Metro. Area Transit Auth., 112 F.3d 1207, 1213 (D.C. Cir. 1997) (reversing ADA and section 504 judgment for deaf plaintiff based on erroneous admission of expert testimony respecting requirements governing police encounters with deaf individuals). See also United States v. Stewart, 433 F.3d 273, 311 (2d Cir. 2006); Nieves-Villanueva v. Soto-Rivera, 133 F.3d 92, 99-100 (1st Cir. 1997) (collecting cases). For the same reason, experts cannot testify that law was clearly established when qualified immunity is at issue. St. Hilaire v. City of Laconia, 71 F.3d 20, 24 (1st Cir.1995); Peterson v. City of Plymouth, 60 F.3d 469, 475 (8th Cir. 1995).
363. Daubert, 509 U.S. at 595 (citations omitted). For example, relying on Rule 403 the court in Nimely v. City of New York, 414 F.3d 381, 397-399 (2d Cir. 2005) recently held in a § 1983 excessive force case that a trial court abused its discretion by admitting expert testimony from a forensic pathologist on witness credibility, or on the tendency of a police officer to misperceive events when using deadly force.
364. See, e.g., Burleson v. Tex. Dep’t of Criminal Justice, 393 F.3d 577 (5th Cir. 2004) (expert witness properly excluded in Eighth amendment claim that defendants exposed plaintiffs to hazardous conditions as prison welder causing him to develop radiation induced cancer; no reliable methodology supported expert’s claim of harmful exposure level).
365. Ellis v. Gallatin Steel Co., 390 F.3d 461, 470 (6th Cir. 2004) (quoting Jahn v. Equine Servs., PSC, 233 F.3d 382, 390 (6th Cir. 2000)). Accord U.S. Information Sys., Inc. v. Int’l Bhd. of Elec. Workers Local Union No. 3, AFL-CIO, 313 F. Supp.2d 213, 235 (S.D.N.Y. 2004) (expert need not “categorically exclude each and every possible alternative cause in order to render the proffered testimony admissible”).
366. Newsome v. McCabe, 319 F.3d 301 (7th Cir. 2003).
367. Champion v. Outlook Nashville, Inc, 380 F.3d 893 (6th Cir. 2004). See also Dickerson v. McClellan, 101 F.3d 1151 (6th Cir. 1996); Kladis v. Brezek, 823 F.2d 1014 (7th Cir. 1987).
368. Champion, 380 F.3d at 907-08, (distinguishing Berry v. City of Detroit, 25 F.3d 1342 (6th Cir. 1994)).
369. Id. at 908 (“The critical difference between testifying about the impact of police policies on a large group of officers and testifying about the proper actions of individual officers in one discreet situation highlights the inapplicability of Berry.”)
370. Thomas v. City of Chattanooga, 398 F.3d 426 (6th Cir. 2005).
372. Id. at 434. See also Gold v. City of Miami, 151 F.3d 1346, 1352 n.13 (11th Cir. 1998) (expert testimony on inherent need for training and supervision in constitutional limits on enforcement of disorderly conduct statute insufficient to support jury verdict in failure to train claim arising from arrest for protected speech; court also held no inference of custom could be drawn from frequency of dismissed or nol prossed arrests absent evidence of reason for those dispositions).
373. Daubert, 509 U.S. at 592 n.10.
374. Cook ex rel. Estate of Tessier v. Sheriff of Monroe County, Fla., 402 F.3d 1092, 1108-1115 (11th Cir. 2005) (affirming exclusion of plaintiff’s expert in § 1983 jail suicide claim for failure of the expert report to show testimony would assist the trier of fact even though report sufficiently established qualifications and reliable methodology, holding that “[p]resenting a summary of a proffered expert's testimony in the form of conclusory statements devoid of factual or analytical support is simply not enough.”)
375. Id. at 1113-14 (“We recognize that a Daubert hearing before the trial court might have given Cook an additional opportunity to meet this burden, but we note that the trial court was under no obligation to hold one,” concluding that decision whether to hold Daubert hearing committed to discretion of trial court).
376. Estate of Moreland v. Dieter, 395 F.3d 747 (7th Cir. 2005) (affirming excessive force judgment against jail guards, holding that defendants waived Daubert objection to expert’s causation testimony by objecting to its admissibility only on hearsay grounds).
377. Fed. R. Evid. 703.
378. Boone v. Moore, 980 F.2d 539, 542 (8th Cir. 1992) (hearsay).
379. Fed. R. Evid. 703.
380. See id. 705.
381. See id. 704(a).
382. See id. 615(3).
383. See, e.g., Malek v. Fed. Ins. Co., 994 F.2d 49, 54 (2d Cir. 1993).
384. Fed. R. Evid. 706.
385. Fed. R. Evid. 803.