In a remarkably detailed and reasoned decision, Justice NeMoyer of Supreme Court, Erie County dissects the holding of Carvalho v New Rochelle Hosp. 53 AD2d 635 [2d Dept 1976].  Carvalho is a seminal case in trial practice, which permits questioning of one party [lawyers as well as doctors] as experts in their own case.

In Grisanti v Kurss ;2010 NY Slip Op 51579(U) ; Decided on September 10, 2010 ; Supreme Court, Erie County ;NeMoyer, J.  writes:
 

""In an action for malpractice brought against more than one physician, one defendant physician may not be examined before trial about the professional quality of the services rendered by a codefendant physician if the questions bear solely on the alleged negligence of the codefendant and not on the practice of the witness . . .. Where, however, the opinion sought refers to the treatment rendered by the witness, the fact that it may also refer to the services of a codefendant does not excuse the defendant witness from [being deposed] as an expert" (Carvalho, 53 AD2d at 635).
Applying those rules, the Carvalho court held it proper for plaintiff’s counsel to ask the first, but proper for the defendant-witness’s counsel to advise the witness not to answer the second, of the following two questions:

1) "[I]s the presence of a fecalith in any way significant to the possibility of the development of an intra-abdominal abscess postoperatively?"; and
2) ""Would it have been good medical practice for a doctor having removed an appendix and receiving this pathology report subsequent to the removal of the appendix to have requested a culture and sensitivity on the purulent exudate material described in the pathology report?"

"This Court has serious misgivings about the provenance (let alone the sense) of the first rule set out in Carvalho, i.e., that the defendant-witness may not be examined before trial about the professional quality of the services rendered by a codefendant physician if the questions bear solely on the alleged negligence of the codefendant and not on the practice of the witness. That rule is not to be found in, and does not seem in the least to be suggested by, either of the two decisions cited by the Second Department in Carvalho (see McDermott v Manhattan Eye, Ear & Throat Hosp., 15 NY2d 20, 27 [1964]; Johnson v New York City Health & Hosps. Corp., 49 AD2d 234 [2d Dept 1975]). McDermott unequivocally holds that "a plaintiff in a malpractice action is entitled to call the defendant doctor to the stand [i.e., at trial] and question him both as to his factual knowledge of the case (that is, as to his examination, diagnosis, treatment and the like) and, if he be so qualified, as an expert for the purpose of establishing the generally accepted medical practice in the community" (McDermott, 15 NY2d at 29-30 [parenthetical material in original; bracketed material supplied]; see Gilly v City of New York, 69 NY2d 509, 511 [1987] [reading McDermott as holding that plaintiff could "examine his doctor-opponent as fully and freely as other qualified witnesses, and that such testimony could include expert opinion"]). In its subsequent decision in Johnson, the Second Department addressed nothing beyond the issue [*6]of whether the McDermott holding "should be extended to examinations before trial," holding that it should, for the common-sense reason "that the scope of the pretrial examination is even broader than that at the trial" (Johnson, 49 AD2d 234, 236-237). Neither McDermott nor Johnson involved a defendant-physician’s being asked to opine specifically on the conduct of a codefendant-physician in relation to the standard of care, and thus neither decision went so far as to say that such opinion would not be a proper area of inquiry of the defendant-witness in a medical malpractice case.

With regard to the internal logic of the Second Department’s holding in Carvalho, it is impossible for this Court to discern why the second Carvalho question ran afoul of the Carvalho rule while the first question did not. Neither of the Carvalho questions referred explicitly to the due care or dereliction of the co-defendant physician; and both questions arguably went to the witness’s knowledge of a particular medical standard within his expertise. With regard to the external logic of the Carvalho holding, both Carvalho questions fell well within the compass of the McDermott-Johnson rule permitting the defendant-witness to be questioned as an expert for the purposes of eliciting his "knowledge of" the facts of plaintiff’s case and "establishing the generally accepted medical practice in the community" (McDermott, 15 NY2d at 29-30; see also Harley v Catholic Med. Ctr. of Brooklyn, 57 AD2d 827, 828 [2d Dept1977] [holding it permissible at EBT to ask defendant-pediatrician about the effects on the infant of certain medicines given by codefendant-obstetrician during the mother’s labor, inasmuch as such questions did not "bear solely on the alleged negligence of the codefendant physician"]).

Apart from the foregoing, this Court has serious doubts that the decision in Carvalho would be rendered today, in the era of 22 NYCRR part 221."