Faulkner v. Arista Records LLC, 2014 U.S. Dist. LEXIS 129711 (S.D.N.Y. Sept. 15, 2014):

"Courts within the Second Circuit have liberally construed expert qualification requirements." In re Methyl Tertiary Butyl Ether ("MTBE") Prods. Liab. Litig., MDL No. 1358 (SAS), 2008 WL 1971538, at *5 (S.D.N.Y. May 7, 2008) (internal quotation marks omitted). "A witness's qualifications 'can only be determined by comparing the area in which the witness has superior knowledge, skill, experience, or education with the subject matter of the witness's testimony.'" In re Fosamax, 645 F. Supp. 2d at 172 (quoting Carroll v. Otis Elevator Co., 896 F.2d 210, 212 (7th Cir. 1990)).

The Advisory Committee's note to Rule 702 explains that the Rule was amended to include the three reliability-based requirements in response to Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993) and its progeny, Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999), and General Elec. Co. v. Joiner, 522 U.S. 136, 146 (1997). See Fed. R. Evid. 702 advisory committee's [*21]  note. In Daubert, the Supreme Court interpreted Rule 702 to require district courts to act as gatekeepers by ensuring that expert scientific testimony "both rests on a reliable foundation and is relevant to the task at hand." 509 U.S. at 597. This requires "a preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts in issue." Id. at 592-93; see also Kumho Tire, 526 U.S. 137 (holding gate keeping function applies to all expert testimony, whether based on scientific, technical or other specialized knowledge).

To be scientifically valid, the subject of expert testimony must rest on "good grounds, based on what is known." Daubert, 509 U.S. at 590 (internal quotation marks omitted). In Daubert, the Court set forth a non-exclusive list of factors that district courts might consider in gauging the reliability of scientific testimony. Id. at 593-95. These factors include: (1) whether the theory has been tested; (2) whether the theory has been subjected to peer review and publication; (3) the known or potential rate of error and whether standards and controls exist and have been maintained with respect to the technique; and (4) the general acceptance of [*22]  the methodology in the scientific community. Id. "Whether some or all of these factors apply in a particular case depends on the facts, the expert's particular expertise, and the subject of his testimony." In re Fosamax, 645 F. Supp. 2d at 173 (citing Kumho Tire, 526 U.S. at 138). A district court has broad discretion both in determining the relevant factors to be employed in assessing reliability and in determining whether that testimony is in fact reliable. Kumho Tire, 526 U.S. at 153; Zuchowicz v. United States, 140 F.3d 381, 386 (2d Cir. 1998).

Weighing whether the expert testimony assists the trier of fact goes primarily to relevance. Daubert, 509 U.S. at 591. Relevance can be expressed as a question of "fit"—"whether expert testimony proffered in the case is sufficiently tied to the facts of the case that it will aid the jury in resolving a factual dispute." Id. (citing United States v. Downing, 753 F.2d 1224, 1242 (3d Cir. 1985)). In addition, expert testimony is not helpful if it simply addresses "'lay matters which a jury is capable of understanding and deciding without the expert's help.'" United States v. Mulder, 273 F.3d 91, 101 (2d Cir. 2001) (quoting United States v. Castillo, 924 F.2d 1227, 1232 (2d Cir. 1991)). Finally, the testimony is not helpful if it "usurp[s] either the role of the trial judge in instructing the jury as to the applicable law or the role of the jury in applying that law to the facts before it." United States v. Duncan, 42 F.3d 97, 101 (2d Cir. 1994) (quoting United States v. Bilzerian, 926 F.2d 1285, 1294 (2d Cir. 1991)).

"In deciding whether a step in an expert's analysis is unreliable, the district court should undertake [*23]  a rigorous examination of the facts on which the expert relies, the method by which the expert draws an opinion from those facts, and how the expert applies the facts and methods to the case at hand." Amorgianos v. Nat'l R.R. Passenger Corp., 303 F.3d 256, 267 (2d Cir. 2002). However, in accordance with the liberal admissibility standards of the Federal Rules of Evidence, only serious flaws in reasoning or methodology will warrant exclusion. Id. "As long as an expert's scientific testimony rests upon 'good grounds, based on what is known,' it should be tested by the adversary process--competing expert testimony and active cross-examination--rather than excluded from jurors' scrutiny for fear that they will not grasp its complexities or satisfactorily weigh its inadequacies." Ruiz-Troche v. Pepsi Cola of Puerto Rico Bottling Co., 161 F.3d 77, 85 (1st Cir. 1998) (quoting Daubert, 509 U.S. at 596); see also Amorgianos, 303 F.3d at 267. If an expert's testimony lies within "the range where experts might reasonably differ," the jury, and not the trial court, should "decide among the conflicting views of different experts." Kumho Tire, 526 U.S. at 153.

"The Daubert analysis focuses on the principles and methodology underlying an expert's testimony, not on the expert's conclusions. In re Fosamax, 645 F. Supp. 2d at 173-74 (citing Daubert, 509 U.S. at 595). However, the Supreme Court in Joiner recognized that "conclusions and methodology are not entirely distinct from one another." 522 U.S. at 146. Therefore, "[a] court may conclude that there is simply too great an analytical gap between the data and the opinion proffered." Id. (stating that "nothing in either Daubert or the Federal Rules of Evidence requir[es] the admission of opinion evidence connected to existing data only by the ipse dixit of the expert.") The ultimate object of the court's gate-keeping role under Rule 702 is 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." Kumho Tire, 526 U.S. at 152. "The flexible Daubert inquiry gives the district court the discretion needed to ensure that the courtroom door remains closed to junk science while admitting reliable expert testimony that will assist the trier of fact." Amorgianos, 303 F.3d at 267. Finally, like all evidence, expert testimony may be excluded under Rule 403 if its "probative value is substantially outweighed by the danger of unfair prejudice, confusion of the issues or misleading the jury, or by considerations of undue delay, waste of time, or needless presentation of cumulative evidence." Fed. R. Evid. 403.