Page 224 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

Toxicology and the Law Chapter | 11 191

VetBooks.ir refers to a set of diseases that physicians consider as possi- medicine. The standards ‘reasonable medical certainty’
and ‘reasonable medical probability’ are also terms of art
ble causes for symptoms the patient is suffering or signs
50
in the law that have no analog for a practicing
that the patient exhibits.
By identifying the likely potential
causes of the patient’s disease or condition and weighing physician.” 55
the risks and benefits of additional testing or treatment, Despite uncertainty in terminology and the complexity
physicians then try to determine the most appropriate that may occur in legal proceedings, a number of state-
approach—testing, medication, or surgery, for example. ments from Justice Breyer in the Introduction to the
Reference Manual on Scientific Evidence follow as his
Veterinary diagnosticians may also be familiar with
thoughts on the current status of and future considerations
the phrase etiological diagnosis, but less so with “differ-
for the increasing need for science in legal proceedings.
ential etiology.”
A judge is not a scientist, and a courtroom is not a scientific
Less commonly, courts often have used the term “differen-
tial etiology” interchangeably with differential diagnosis. 51 laboratory. But consider the remark made by the physicist
Wolfgang Pauli. After a colleague asked whether a certain
In medicine, etiology refers to the study of causation in dis-
ease, 52 but differential etiology is a legal invention not scientific paper was wrong, Pauli replied, “That paper isn’t
even good enough to be wrong!” Our objective is to avoid
used by physicians. In general, both differential etiology
legal decisions that reflect that paper’s so-called science.
and differential diagnosis are concerned with establishing
The law must seek decisions that fall within the boundaries
or refuting causation between an external cause and a
of scientifically sound knowledge. 56
plaintiff’s condition. Depending on the type of case and the
legal standard, a medical expert may testify in regard to Despite the difficulties, I believe there is an increasingly
specific causation, general causation, or both. General cau- important need for law to reflect sound science. I remain
optimistic about the likelihood that it will do so. ... 57
sation refers to whether the plaintiff’s injury could have
been caused by the defendant, or a product produced by the The judiciary, too, has begun to look for ways to
defendant, while specific causation is established only when improve the quality of the science on which scientifically
the defendant’s action or product actually caused the harm. related judicial determinations will rest. ... 58
53
An opinion by a testifying physician may be offered in Moreover, our Court has made clear that the law
support of both kinds of causation. 54 imposes on trial judges the duty, with respect to scientific
evidence, to become evidentiary gatekeepers. 59 The judge,
The meaning of “certainty” may be uncertain. The ref-
erence guide states: “Courts also refer to medical cer-
tainty or probability in ways that differ from their use in
55. See, e.g., Dallas v. Burlington N., Inc., 689 P.2d 273, 277 (Mont.
1984) (“‘[R]easonable medical certainty’ standard; the term is not well
50. Reference guide citing Steadman’s Medical Dictionary 531 (28th ed. understood by the medical profession. Little, if anything, is ‘certain’ in
2006) (defining differential diagnosis as “the determination of which of science. The term was adopted in law to assure that testimony received
two or more diseases with similar symptoms is the one from which the by the fact finder was not merely conjectural but rather was sufficiently
patient is suffering, by a systematic comparison and contrasting of the probative to be reliable”). This reference guide will not probe substantive
clinical findings.”). legal standards in any detail, but there are substantive differences in
51. Reference guide citing See Proctor v. Fluor Enters., Inc. 494 F.3d admissibility standards for medical evidence between federal and state
1337 (11th Cir. 2007) (testifying medical expert employed differential courts. See Robin Dundis Craig, When Daubert Gets Erie: Medical
etiology to reach a conclusion regarding the cause of plaintiff’s stroke). Certainty and Medical Expert Testimony in Federal Court, 77 Denv. U.
But see McClain v. Metabolife Int’l, Inc., 401 F.3d 1233, 1252 (11th L. Rev. 69 (1999).
Cir. 2005) (distinguishing differential diagnosis from differential etiol- 56. Introduction--Stephen Breyer.” National Research Council. 2011.
ogy, with the former closer to the medical definition and the latter Reference Manual on Scientific Evidence: Third Edition. Washington,
employed as a technique to determine external causation). DC: The National Academies Press. doi: 10.17226/13163. Referencing
52. Reference guide citing Steadman’s Medical Dictionary 675 (28th ed. 7. Peter W. Huber, Galileo’s Revenge: Junk Science in the Courtroom
2006) (defining etiology as “the science and study of the causes of dis- 54 (1991).
ease and their mode of operation....”). For a discussion of the term “eti- 57. Introduction--Stephen Breyer.” National Research Council. 2011.
ology” in epidemiology studies, see Michael D. Green et al., Reference Reference Manual on Scientific Evidence: Third Edition. Washington,
Guide on Epidemiology, Section I, in this manual. DC: The National Academies Press. doi: 10.17226/13163.
53. Reference guide citing See Amorgianos v. Nat’l R.R. Passenger 58. Introduction--Stephen Breyer.” National Research Council. 2011.
Corp., 303 F.3d 256, 268 (2d Cir. 2002). Reference Manual on Scientific Evidence: Third Edition. Washington,
54. Reference guide citing See, e.g., Ruggiero v. Warner-Lambert Co. DC: The National Academies Press. doi: 10.17226/13163.
424 F.3d 249 (2d Cir. 2005) (excluding testifying expert’s differential 59. Gen. Elec. Co. v. Joiner, 522 U.S. 136 (1997); Daubert v. Merrell
diagnosis in support of a theory of general causation because it was not Dow Pharms., Inc., 509 U.S. 579 (1993). A description of the program
supported by sufficient evidence). can be found at Committee on Science, Technology, and Law.