An experienced practicing physician is a medical expert, and it is not required that he or she be a specialist in the particular malady at issue in order to make his or her testimony as an expert admissible. The weight to be given to the expert testimony of a treating physician, however, is for the trier of fact to determine.31 Physical condition and causation of injury or death (when not of a character obvious without a medical opinion), medical diagnoses, treatment of an injury or illness or the effect or extent of an injury or disease may be presented only by expert testimony.32
A medical expert may not speculate as to the possible medical causes or consequences, but must limit the testimony to establishing causes or consequences that are reasonably probable.33 In Delaware, physicians have always been permitted to state their conclusion that the injury or death was or was not caused by the given accident or event. However, medical opinions based solely on statistics, without specific study of the patient, lack the individual considerations which are essential to a medical determination and so are inadmissible.34
The Superior Court has permitted expert testimony to show the latent psychological effect of pornography on the unconscious mind, but not to show its effect on the conscious mind.35
By statute in criminal cases where the defendant is asserting a defense of mental illness, psychiatric disorder or emotional distress 36, a psychiatrist or other expert testifying at trial about the mental condition of a defendant may testify as to (i) the nature of the examination, (ii) the mental condition of the defendant at the time the crime was committed, and (iii) the defendant’s capacity, if any, to appreciate the wrongfulness of his or her conduct or to choose whether he or she would do the act or refrain from doing the act or whether the defendant had a particular state of mind which is an element of the crime charged, or whether the defendant had a mental illness or mental defect at the time of the commission of the crime.37
Expert testimony generally is required to show the standard of care utilized and expected in the medical profession as well as others.38 Where the challenged action of a doctor or other professional is of such an extreme character that non-experts can determine that the action exceeds a reasonable standard of care, however, expert testimony is not required to establish the benchmark by which the standard of care is measured.39 Similarly, if the action of a doctor or other professional did not involve professional error, but rather a failure to exercise the level of due care expected of all people, such as the failure to follow written instructions, expert testimony is not necessary.40
When a medical expert offers an opinion it should be stated in terms of a “reasonable medical certainty” or a “reasonable medical probability.”41 However, there is no obligation to couch their opinions in legal terms or to articulate the standard of care with a high degree of legal precision or with “magic words.”42
Chiropractors may testify as medical experts concerning matters within the scope of their profession and the practice of chiropractic.43
31. Clements v. Diamond State Port Corp., 831 A.2d 870, 877 (Del. 2003); DiSabatino Brothers, Inc. v. Wortman, 453 A.2d 102, 106 (Del. 1982).
32. Money v. Manville Corp. Asbestos Disease Compensation Trust Fund, 596 A.2d 1372, 1376-77 (Del. 1991); Wright v. State, 374 A.2d 824, 829 (Del. 1977); Christian v. Wilmington General Hospital Asso., 135 A.2d 727, 730 (Del. 1957); Friedel v. Osunkoya, 994 A.2d 746, 760 (Del. Super. 2010); Lee v. A.C. & S. Co., 542 A.2d 352, 355-56 (Del. Super. 1987); McCormick Transp. Co. v. Barone, 89 A.2d 160, 163 (Del. Super. 1952); Moore v. Perdue Farms, Inc., C.A. No. 88A-FE-4, slip op. 7, Graves, J. (Del. Super. Apr. 30, 1990); Rea v. Midway Realty Corp., C.A. No. 88C-JL6, slip op. at 3, Graves, J. (Del. Super. Mar. 14, 1990). See also Mountaire of Delmarva, Inc. v. Glacken, 487 A.2d 1137, 1141 (Del. 1984).
33. Money v. Manville Corp. Asbestos Disease Compensation Trust Fund, 596 A.2d 1372, 1377 (Del. 1991); Oxendine v. State, 528 A.2d 870, 873 (Del. 1987); Dutton v. State, 452 A.2d 127, 141 (Del. 1982) (expert testimony necessary where cause of death is not susceptible of explanation based on common observation or experience); Riegel v. Aastad, 272 A.2d 715, 718 (Del. 1970); Air Mod Corp. v. Newton, 215 A.2d 434, 438 (Del. 1965); General Motors Corp. v. Freeman, 164 A.2d 686, 688-89 (Del. 1960).
34. Lee v. A.C. & S. Co., 542 A.2d 352, 355-56 (Del. Super. 1987).
35. State v. Scope, 86 A.2d 154, 157-58 (Del. Super. 1952).
36. See § 4:11.
37. 11 Del. C. § 402(b). Thus, Delaware does not follow Federal Rule of Evidence 704(1), which precludes an expert from testifying at trial as to whether a defendant did or did not have the mental state that is an element of a defense to a crime. State v. Magner, ID #9509007746, slip op. at 20, Alford, J. (Del. Super. Mar. 7, 1997).
38. See 18 Del. C. § 6854 (medical); Seiler v. Levitz Furniture Co. of Eastern Region, Inc., 367 A.2d 999, 1008 (Del. 1976) (construction design); Larrimore v. Homeopathic Hospital Asso., 181 A.2d 573, 577 (Del. 1962) (medical); Christian v. Wilmington General Hospital Asso., 135 A.2d 727, 730 (Del. 1957) (medical); Red Clay Consol. School Dist. v. Lamb, C.A. No. 87A-NO-3, slip op., at 5-6, Taylor, J. (Del. Super. Oct. 14, 1988) (ORDER) (medical); Ramada Inns v. Dow Jones & Co., C.A. No. 83C-AV-56, slip op. at 11-12, Poppiti, J. (Del. Super. Mar. 10, 1988) (journalism). See also Baoust v. Kraut, 377 A.2d 4, 7 (Del. 1977). Note: 18 Del. C. § 6853 creates three instances of medical misconduct which create an inference of negligence such that expert testimony is not required: (i) where a foreign object is intentionally left within the body of the patient following surgery, (ii) where an explosion or fire originating in a substance used in treatment occurs in the course of treatment, and (iii) where a surgical procedure is performed on the wrong patient or the wrong organ, limb or part of the patient’s body. Walls v. Cooper, No. 209, 1991, slip op. at 10, Christie, J. (Del. Nov. 8, 1991) (ORDER), disposition reported at 604 A.2d 419 (Del. 1991) (TABLE), cert. denied, 503 U.S. 1006 & 504 U.S. 919 (1992).
39. Seiler v. Levitz Furniture Co. of Eastern Region, Inc., 367 A.2d 999, 1008 (Del. 1976); Larrimore v. Homeopathic Hospital Asso., 181 A.2d 573, 577 (Del. 1962); Christian v. Wilmington General Hospital Asso., 135 A.2d 727, 730 (Del. 1957); Hornbeck v. Homeopathic Hospital Asso., 197 A.2d 461, 464 (Del. Super. 1964).
40. Larrimore v. Homeopathic Hospital Asso., 181 A.2d 573, 577 (Del. 1962).
41. Perkins v. State, 920 A.2d 391, 395 (Del. 2007); Whittaker v. Houston, 888 A.2d 219, 223-224 (Del. 2005); Floray v. State, 720 A.2d 1132, 1136 (Del. 1998).
42. Green v. Weiner, 766 A.2d 492, 495 (Del. 2001).
43. Whittaker v. Houston, 888 A.2d 219, 222-223 (Del. 2005).
© 2010 David L. Finger