In order for an expert witness to be qualified, he or she must be suitably qualified and possessed of sufficient specialized knowledge to be able to express an expert opinion and to explain the basis of that opinion

Law Lessons from ELLIOT ROJAS VS. RIFKY RUBENSTEIN AND 208-210 PARKER CORPORATION, ET AL., App. Div., A-5755-10T2, October 18, 2012:

N.J.R.E. 702 allows a witness qualified as an expert to offer opinion testimony “[i]f scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue[.]”
There are three requirements that must be met before expert testimony may be admitted:

(1) the intended testimony must concern a subject matter that is beyond the ken of the average juror; (2) the field testified to must be at a state of the art such that an expert’s testimony could be sufficiently reliable; and (3) the witness must have sufficient expertise to offer the intended testimony.

[Hisenaj v. Kuehner, 194 N.J. 6, 15 (2008). See also Biunno, Weissbard & Zegas, Current N.J. Rules of Evidence, comment 1 on N.J.R.E. 702 (2012).]

The decision whether to admit expert testimony is “remitted to the sound discretion of the trial court. Absent a clear abuse of discretion, an appellate court will not interfere with the exercise of that discretion.” Carey v. Lovett, 132 N.J. 44, 64 (1993). A discretionary decision on the qualifications of an expert may be reviewed for “manifest error and injustice.” State v. Torres, 183 N.J. 554, 572 (2005).

Expert testimony is not required when the subject can be readily understood by jurors utilizing their common knowledge and experience, provided it is not beyond the “ken of the average juror.” State v. Harvey, 121 N.J. 407, 426-27 (1990), cert. denied, 499 U.S. 931, 111 S. Ct. 1336, 113 L. Ed. 2d 268 (1991). A topic is beyond the ken of the jury and requires expert testimony to support the claim only “when the subject matter to be dealt with ‘is so esoteric that jurors of common judgment and experience cannot form a valid judgment as to whether the conduct of the party was reasonable.'” Rocco v. N.J. Transit Rail Operations, Inc., 330 N.J. Super. 320, 341 (App. Div. 2000) (quoting Butler v. Acme Mkts., Inc., 89 N.J. 270, 283 (1982)).

Generally, experts are needed to establish the standard of care, such as in malpractice cases, because the jury lacks the “‘requisite special knowledge, technical training and background[.]'” Kelly v. Berlin, 300 N.J. Super. 256, 265 (App. Div. 1997) (quoting Rosenberg ex rel. Rosenberg v. Cahill, 99 N.J. 318, 325 (1985)). “Experts are not needed to establish the appropriate professional standards of care where either the doctrine of res ipsa loquitur or the doctrine of common knowledge applies.” Kelly, supra, 300 N.J. Super. at 265. An expert is not needed, under the common knowledge doctrine, when the issue of negligence is not technical and the “‘carelessness of the defendant is readily apparent to anyone of average intelligence and ordinary experience.'” Id. at 265-66 (quoting Rosenberg, supra, 99 N.J. at 325). In that circumstance, the trial would be “essentially no different from ‘an ordinary negligence case.'” Kelly, supra, 300 N.J. Super. at 266 (quoting Rosenberg, supra, 99 N.J. at 325).

When the plaintiff’s case requires expert testimony to determine the accepted standard of care, the trial court may dismiss the case at the end of the plaintiff’s case if there is either no expert testimony or inadequate expert testimony. Hearon v. Burdette Tomlin Mem’l Hosp., 213 N.J. Super. 98, 104 (App. Div. 1986).

In order for an expert witness to be qualified, he or she “must be suitably qualified and possessed of sufficient specialized knowledge to be able to express [an expert opinion] and to explain the basis of that opinion.” State v. Moore, 122 N.J. 420, 458-59 (1991) (alteration in original) (internal quotation marks and citation omitted). The Supreme Court has noted that “trial courts take a liberal approach when assessing” the qualifications of an expert. State v. Jenewicz, 193 N.J. 440, 454 (2008). “Our case law is replete with examples of the generous approach taken by our courts when qualifying experts based on training and experience.” Ibid. See also Torres, supra, 183 N.J. at 572 (noting an “expert may be qualified on the basis of his experience, even when it is limited”).

Moreover, any perceived deficiencies, “thinness and other vulnerabilities in an expert’s background” or qualifications may “be explored through cross-examination[.]” Jenewicz, supra, 193 N.J. at 455. “That the strength of an individual’s qualifications may be undermined through cross-examination is not a sound basis for precluding an expert from testifying . . . even if it likely will affect the weight that the jury will give the opinion.” Ibid. Instead, “a court should simply be satisfied that the expert has a basis in knowledge, skill, education, training, or experience to be able to form an opinion[.]” Ibid. Furthermore, “[i]t is the unique role of the jury to assess the credibility of the witnesses and the weight to be given to their testimony. Expert testimony is treated no differently, and . . . [the jury is] not bound to accept an expert’s opinion in whole or even in part.” City of Long Branch v. Liu, 203 N.J. 464, 491 (2010).

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