Litigation, especially legal malpractice litigation, requires specialized, specific, admissible proof of each of the prima facie elements of each cause of action. In a legal malpractice case the pleadings must support the cause of action. Later, either at summary judgment or on plaintiff’s case, an expert must give admissible testimony which supports the cause of action.

To support the cause of action at either summary judgment or the trial stage, the expert (for either side) must set forth the appropriate standard of care so that the trier of fact may determine whether there had been a departure from the appropriate standard of care. The expert often has to further opine whether plaintiff could have obtained a better result in the underlying case (“but for”). Because the subject matter of the legal malpractice is itself litigation, the expert might have to testify that had there been no departure, plaintiff would have succeeded in the underlying case. This article will discuss some aspects of what expert testimony is admissible, what testimony is permissible, and what testimony is persuasive.


Courts have a gatekeeping role in expert witness presentation. In federal cases, under Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993), and pursuant to Rule 702, the court must assure that testimony offered proceeds from relevant, reliable, empirically tested opinions based upon sufficient facts or data, and is the product of reliable principles and methods which have been applied to the facts of the case.

In New York state cases, Frye v. United States, 293 F. 1013 (D.C.Cir. 1923) and its progeny require that opinion evidence must have graduated from the experimental to the established and generally accepted standard. New York courts follow Frye. Giordano v. Market Am., 15 NY3d 590 (2010). The question is generally whether there is a proper foundation to determine that the accepted methods were appropriately employed in a particular case. Parker v. Mobil Oil, 7 NY3d 434 (2006). If accepted methods have been followed by the expert seeking to offer an opinion in a legal malpractice case, then the opinions are permissible.

Recovery for legal malpractice requires proof of three elements: (1) the negligence of an attorney; (2) that the negligence was the proximate cause of the loss sustained; and (3) proof of actual damages. It further requires plaintiff to establish that counsel “failed to exercise the ordinary reasonable skill and knowledge commonly possessed by a member of the legal profession” and that “‘but for’ the attorney’s negligence” the plaintiff would have prevailed in the matter or would have avoided damages. Ulico Cas. v. Wilson, Elser, Moskowitz, Edelman & Dicker, 56 AD3d 1 (1st Dept. 2008); Rudolph v. Shayne, Dachs, Stanisci, Corker & Sauer, 8 NY3d 438 (2007). Expert opinion on the standard of care which was to be followed, and on whether “but for” the negligence plaintiff could have succeeded is permissible. Opinion evidence beyond those parameters (as discussed below) is impermissible.


Beyond the scope of this article are the expert witness disclosure provisions of CPLR 3101. As is well understood in the trial community, there are elastic time requirements for disclosure of the name, qualifications, opinions and basis for the opinions under CPLR 3101. As an overlay, or exception to that understanding, some courts have held that the expert must be disclosed prior to a motion for summary judgment or a party may be precluded from offering expert opinion on the motion. In general, prior to trial, the party seeking to offer expert testimony must identify the expert by name, give “in reasonable detail the subject matter” as well as “the substance of the facts and opinions” on which the expert is expected to testify and a “summary of the grounds” for the opinion. Manzanares v. ATM Four, 2012 NY Slip Op 30998U. The qualifications of the expert must also be given. CPLR 3101(d).

What Makes an Expert?

Experts in legal malpractice litigation must show that they have the knowledge of the law and attorney practice in New York sufficient to satisfy Frye. Legal malpractice experts are those attorneys who are admitted to practice in the courts of the State of New York, or can demonstrate sufficient knowledge of the laws and practices in the State of New York so as to be recognized as a person knowledgeable of the standard of practice in the legal community. Prior to trial, the party seeking to offer expert testimony must identify the expert by name, give “in reasonable detail the subject matter” as well as “the substance of the facts and opinions” on which the expert is expected to testify and a “summary of the grounds” for the opinion. Manzanares, supra. The qualifications of the expert must also be given. CPLR 3101(d).

With only a very few exceptions, there is no “specialization” in the field of law. Unlike the field of medicine, there are but three “Boards” which are permitted to offer certification. Boards give certification in DWI litigation, in medical malpractice litigation and in legal malpractice litigation. Persons certified as members of these boards, which is earned in the same manner as by physicians, are permitted to call themselves “specialists.” Patent attorneys historically have the same right.

One major source of expert admissibility disputes in medical malpractice is whether the expert is sufficiently familiar with the specialty of the party about whom he or she testifies. With only the patent law exception, no such dispute can genuinely arise in legal malpractice litigation. The expert’s qualifications are always open to impeachment, but the court will not seriously entertain a motion to disqualify as it might if a dermatologist were to comment upon a cardiologist.

At trial, the experience of the expert is fodder for cross-examination, as is the ” quality” of the opinion, communications between expert and counsel, and the material reviewed for the opinion.

When Is an Expert Necessary?

Experts are necessary for three purposes. One is for the attorney and two are for the case. Legal malpractice attorneys may not have experience in the substantive subject matter of the underlying case and may need guidance. Assume that a patent was applied for, and then denied because the application was deficient. It’s easy to opine that making mistakes in a patent application is legal malpractice. But, what was the mistake? Was it a failure to account for “prior art”? Was it something else? What is prior art? How is it important? How does the able practitioner deal with it? What does the existence of prior art imply? These are all issues that an expert must explain to the legal malpractice plaintiff’s attorney, giving the attorney enough information to compose an adequate complaint. This is expert material that is of use to the attorney.

Expert testimony is generally required to establish a breach of the standard of professional care, except where the daily experience of the fact finder provides a sufficient basis for judging the adequacy of the professional service. Expert opinion testimony that a defendant’s representation of a plaintiff departed from the appropriate standard of care exercised by attorneys in the community is an essential element in a legal malpractice action. “In order to make out a prima facie case that an attorney’s conduct has breached the duty of care, a plaintiff must generally present expert testimony establishing the applicable standard of care from which the defendant allegedly deviated.” Merlin Biomed Asset Mgmt. v. Wolf Block, Schoor & Solis-Cohen, 5 Misc3d 1011A (Sup Ct., New York Co. 2004).

There are two exceptions: when the attorney’s conduct falls below any standard of due care, and where a juror’s ordinary experience would provide sufficient basis for judging the adequacy of the professional service. These exceptions are usually elementary and include such things as failing to file an answer, failing to commence an action within the statute of limitations, and failing to appear in court. Estate of Nevelson v. Carro, Spanbock, Kaster & Cuiffo, 259 AD2d 282 (1st Dept. 1999).

One should expect a motion for summary judgment in every legal malpractice case. If the motion does not challenge the “departures” it will question the “but for” portion of the complaint. In order to succeed at a motion for summary judgment in a legal malpractice case defendant must demonstrate that plaintiff is unable to prove at least one of the elements of the cause of action. Scartozzi v. Potruch, 72 AD3d 787 (2d Dept. 2010); Boglia v. Greenberg, 63 AD3d 973 (2d Dept. 2009).


A plaintiff must generally present expert testimony establishing the standard of practice applicable to defendant so that the trier of fact may determine whether there had been a departure from that standard. Expert witnesses should not offer opinions as to the ultimate legal obligations of parties. That is an issue to be determined by the trial court. “Expert opinion as to a legal conclusion is impermissible.” Colon v. Rent-A-Center, 276 AD2d 58 (1st Dept. 2000).

What is the difference between an opinion on the standards of practice and how a particular defendant practiced and the “legal conclusion”? The expert may state what he believes the standard of practice to be but “may not be utilized to offer opinion as to the legal standards which he believes should have governed a party’s conduct. We do not rely on an attorney’s affidavits to tell us what constitutes malpractice.” Wo Yee Hing Realty v. Stern, 30 Misc.3d 1237A (Sup Ct., New York Co. 2011) What then is the real difference?

In Colon the expert testified as to the “legal obligations of parties under a contract.” That issue was reserved for the trial court, and constituted impermissible expert opinion as to a legal conclusion. It would have been permissible if the expert testified to the actual obligations stated in the contract and then offered an opinion whether the party met those contractual obligations. The trial court could then have charged the jury as to the legal consequence of a party not meeting obligations in the contract and how to evaluate a failure to meet those contractual obligations.

Since expert testimony is required to establish the applicable standard of care (see Estate of Nevelson v. Carro, Spanbock, Kaster & Cuffo, supra), with the finder of fact deciding whether there was a deviation from such standard, the expert has to skirt the line of opining that the defendant committed malpractice. The farthest point generally permitted to the expert is that the standard of practice is “A.” Defendant failed to meet standard “A” and fell short. The court then tells the jury that if the defendant fell short of good practice, he may be found to have committed malpractice, with the jury to determine proximate cause and “but for.” PJI 2:152. An attorney must “exercise that degree of care, skill and diligence commonly possessed by a member of the legal profession.” The expert is permitted to set forth his opinion of the “care, skill and diligence commonly possessed by a member of the legal profession” and relate the acts of the defendant to those standards.

Of course in determining whether malpractice occurred, “an attorney is not held to the rule of infallibility and is not liable for an honest, mistake of judgment, where the proper course is open to reasonable doubt” Bernstein v. Oppenheim, 160 AD2d 428, 430 [1st Dept. 1990]). “Absent such ‘reasonable’ courses of conduct found as a matter of law, a determination that a course of conduct constitutes malpractice requires findings of-fact.” Id.

Calling the Expert at Trial

Direct examination of an expert can either be an example of the highest form of trial skills, or it can be akin to starting an engine and allowing it to govern itself. Attorney experts as well as doctor experts are recognized for their tendency to take over the narrative. A primer on direct examination of an expert is well outside the scope of this article, but it should be remembered that all opinions are offered “with a reasonable degree of legal certainty” and that the expert must state the standard of practice within the community, and the standard must be stated with both certainty and specificity. The superior witness will cite examples of such practice, and will do so in a manner that engages the jury.


An expert in legal malpractice is necessary, helpful and essential. Their opinion is an essential element of the proof of legal malpractice, and except in a very narrow set of departures, will be the fulcrum upon which a decision of whether or not there has been a departure that proximately damaged plaintiff will be determined.

Andrew Lavoott Bluestone is an attorney in Manhattan, specializing in legal malpractice litigation. He is board certified in legal malpractice by the American Board of Professional Liability Attorneys.