It is not uncommon to get in an expert report from the other side that makes you scratch your head.  Maybe it is well written  Maybe it is very interesting.  Hopefully the math is right.  Maybe it is even very persuasive.  The reason why you are scratching your head, however, is that the factual basis of the report seems to have bare no relation to the actual, provable facts of the case.  Rather, the report relies on supposition, innuendo, theory, hypothetical facts, etc.  What it doesn’t rely on, however, is the actual facts of your case.

24082729_sSo what do we do?  We complain to the judge and maybe even file a motion to strike the report.  As lawyers, how often have we heard judges fudge the application of the rules of evidence and dismissively say, “I’ll let it in – your objection goes to the weight”?  That said, if it is true “net opinion” -meaning an expert opinion that cannot be relied upon, the objection is about whether the report and testimony in the first place, and not what weight the judge, as the trier of fact gives to it.

Yesterday, the Supreme Court reminded us what the proper standard is, and more importantly, that an expert report must be based upon the evidence in the case, in the case of Townsend v. Pierre.  Though this was a personal injury case, the same principles apply to family law cases. The facts in that case are not relevant for this discussion except for the fact that the ultimate facts were not in dispute.

As to expert opinions and net opinions, the Supreme Court reminded us that:

N.J.R.E. 703 addresses the foundation for expert testimony. It mandates that expert opinion be grounded in “‘facts or data derived from (1) the expert’s personal observations, or (2) evidence admitted at the trial, or (3) data relied upon by the expert which is not necessarily admissible in evidence but which is the type of data normally relied upon by experts.’” Polzo, supra, 196 N.J. at 583 (quoting State v. Townsend, 186 N.J. 473, 494 (2006)). The net opinion rule is a “corollary of [N.J.R.E. 703] . . . which forbids the admission into evidence of an expert’s conclusions that are not supported by factual evidence or other data.” Ibid. The rule requires that an expert “‘give the why and wherefore’ that supports the opinion, ‘rather than a mere conclusion.’” Borough of Saddle River v. 66 E. Allendale, LLC, 216 N.J. 115, 144 (2013) (quoting Pomerantz Paper Corp., supra, 207 N.J. at 372); see also Buckelew, supra, 87 N.J. at 524 (explaining that “an expert’s bare conclusion[], unsupported by factual evidence, is inadmissible”).  …

The Court went on to note that:

The net opinion rule, however, mandates that experts “be able to identify the factual bases for their conclusions, explain their methodology, and demonstrate that both the factual bases and the methodology are reliable.” Landrigan, supra, 127 N.J. at 417. An expert’s conclusion “‘is excluded if it is “‘based merely on unfounded speculation and unquantified possibilities.’” Grzanka v. Pfeifer, 301 N.J. Super. 563, 580 (App. Div. 1997) (quoting Vuocolo v. Diamond Shamrock Chem. Co., 240 N.J. Super. 289, 300 (App. Div.), certif. denied, 122 N.J. 333 (1990)), certif. denied, 154 N.J. 607 (1998). As the Appellate Division noted, when an expert speculates, “he ceases to be an aid to the trier of fact and becomes nothing more than an additional juror.” Jimenez v. GNOC, Corp., 286 N.J. Super. 533, 540 (App. Div.), certif. denied, 145 N.J. 374 (1996), overruled on other grounds, Jerista v. Murray, 185 N.J. 175 (2005). By definition, unsubstantiated expert testimony cannot provide to the factfinder the benefit that N.J.R.E. 702 envisions: a qualified specialist’s reliable analysis of an issue “beyond the ken of the average juror.” Polzo, supra, 196 N.J. at 582 (citations omitted); see N.J.R.E. 702. Given the weight that a jury may accord to expert testimony, a trial court must ensure that an expert is not permitted to express speculative opinions or personal views that are unfounded in the record.

We next turn to the issue on about the use of hypothetical questions in expert testimony.  Under the Rules of Evidence, while lay witnesses are not permitted to be asked hypothetical questions, experts can.  However, the court made clear that the hypotheticals must relate to the evidence, as follows:

The use of hypothetical questions in the presentation of expert testimony is permitted by N.J.R.E. 705, “provided that the questions include facts admitted or supported by the evidence.” Biunno, Weissbard & Zegas, Current N.J. Rules of Evidence, comment 4 on N.J.R.E. 705 (2014) (citing Wilsey v. Reisinger, 76 N.J. Super. 20, 25 (App. Div.), certif. denied, 38 N.J. 610 (1962)). As this Court noted in Stanley Co. of America v. Hercules Powder Co., “[t]he opinions of experts must be based either upon facts within their own knowledge which they detail to the jury or upon hypothetical questions embracing facts supported by the evidence upon which the expert opinion is sought.” 16 N.J. 295, 305 (1954) (citing Beam v. Kent, 3 N.J. 210, 215 (1949)); see also Savoia v. F. W. Woolworth Co., 88 N.J. Super. 153, 162 (App. Div. 1965). “Expert opinion is valueless unless it is rested upon the facts which are admitted or are proved.” Stanley, supra, 16 N.J. at 305 (citing Bayonne v. Standard Oil Co., 81 N.J.L. 717, 722 (E. & A. 1910)); see also State v. Sowell, 213 N.J. 89, 100 (2013) (holding that hypothetical question in criminal case must be limited to facts presented at trial); accord State v. Nesbitt, 185 N.J. 504, 519 (2006); State v. Odom, 116 N.J. 65, 78-79 (1989). Consequently, “a hypothetical question cannot be invoked to supply the substantial facts necessary to support the conclusion.” Stanley, supra, 16 N.J. at 305 (citations omitted); Wilsey, supra, 76 N.J. Super. at 25.

The last sentence of this quote bares repeating, a hypothetical questions cannot be used to supply facts necessary to support the expert’s conclusion where those facts don’t actually exist in the case.

The takeaway here is that attorneys should consider making motions to strike expert reports that are not based upon the provable facts that can be adduced at trial or at least be prepared to address this point at trial.


Eric SolotoffEric Solotoff is the editor of the New Jersey Family Legal Blog and the Co-Chair of the Family Law Practice Group of Fox Rothschild LLP. Certified by the Supreme Court of New Jersey as a Matrimonial Lawyer and a Fellow of the American Academy of Matrimonial Attorneys, Eric is resident in Fox Rothschild’s Roseland and Morristown, New Jersey offices though he practices throughout New Jersey. You can reach Eric at (973)994-7501, or
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