Page 213 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

180 SECTION | I General

VetBooks.ir to Good Laboratory Practice standards, 23 and many state assurance samples, method validation, split sample test-
ing, and other such procedures in laboratories.
agencies have state specific data practices requirements.
Analytical toxicologists know the limits of interpreta-
While the specific requirements may vary, the general
purpose is to authenticate the accuracy of the document tion of the results of a given test. However, some who see
produced, such as a final report. these reports may not. So toxicologists may take care in
The case report and the documents supporting that the wording of interpretive comments made.
case report may be required to authenticate that report in
a legal proceeding. Authentication of case documents is Testimony
one reason that many laboratories have established record
retention procedures. A document and its underlying sup- Testimony is a third means of introducing evidence.
port may be retained for 7 years in some diagnostic labo- Testimony is often gathered during the discovery portion
ratories. The specimens themselves are also important in of a legal case by taking the deposition of witnesses.
these proceedings. Testimony may also be given orally at trial. Witnesses are
under oath both at the deposition and at trial. Testimony
Specimens given in a deposition may be entered into evidence at trial.
This is sometimes done because the witness is not avail-
Specimens are often relevant in toxicology cases. able for the trial date. The same person on the same sub-
Toxicologists are well aware of the importance of accurate ject may give testimony in a deposition, then again at trial.
sample identification to establish the relevance of the results Testimony is given by both “lay” witnesses and expert
of testing a particular sample. Laboratories involved in rac- witnesses. Admission of testimony from a lay witness is
ing chemistry, regulatory enforcement, GLP studies or normally evaluated differently than that of an expert wit-
cGMP analyses often have significant sample tracking ness. A lay witness must have personal knowledge of the
documents to establish that the result of a test can be facts to which she or he is testifying. Specifically, “[a]
tracked to a specific original specimen or sample. These witness may not testify to a matter unless evidence is
sample tracking or chain of custody documents are often introduced sufficient to support a finding that the witness
needed to establish that the sample tested does, in fact, has personal knowledge of the matter. Evidence to prove
relate to the case report. The absence of sample tracking, or personal knowledge may, but need not, consist of the
appropriate chain of custody data, may eviscerate submis- witness’ own testimony. ...” Rule 602
sion of the report of that testing as evidence in a case. The Lay witnesses must testify to their personal knowl-
federal judicial system is aware of this as well. It considers edge. This personal knowledge is their recollection of the
as relevant evidence “comparison by the trier of fact or by event. For example, the animal owner in our hypothetical
expert witnesses with specimens which have been authenti- example may testify that she did purchase the feed, that
cated.” Rule 901, (3) Split sample testing in racing chemis- she fed it to her animals, that she observed certain clinical
try laboratories may be an example of comparison by an signs including death in her animal(s), and that she deliv-
expert witness with authenticated samples. Such split sam- ered a dead animal to the veterinary diagnostic laboratory.
ple testing may also be desirable in toxicology cases that The animal owner may be cross examined to help ver-
reach an insurance claim, civil or criminal case level. ify details of the events. The animal owner’s recollection
Toxicologists and analytical chemists are aware of the may be refreshed by referring to a written document, for
potential for different results when different analytical example, pursuant to Rule 612. 24
methods are used. This awareness has given rise over the
years to recognition of the need to “validate” tests and
24. “Except as otherwise provided in criminal proceedings by section
test results. The federal judicial system is also aware of 3500 of title 18, United States Code, if a witness uses a writing to refresh
this need. It requires “[e]vidence describing a process or memory for the purpose of testifying, either—
system used to produce a result and showing that the pro- (1) while testifying, or
cess or system produces an accurate result.” Rule 901, (9) (2) before testifying, if the court in its discretion determines it is neces-
AOACI is an example of an entity that may validate an sary in the interests of justice,
analytical method for a particular matrix. Normally the an adverse party is entitled to have the writing produced at the hearing,
plaintiff has the burden of persuading the judge that the to inspect it, to cross-examine the witness thereon, and to introduce in
evidence those portions which relate to the testimony of the witness. ...
analytical results go with the correct sample, and the
If a writing is not produced or delivered pursuant to order under this
results of that sample’s testing are on the correct report.
rule, the court shall make any order justice requires, except that in crimi-
Authenticating sample results for such proceedings is one
nal cases when the prosecution elects not to comply, the order shall be
reason for standard operating procedures, quality one striking the testimony or, if the court in its discretion determines that
the interests of justice so require, declaring a mistrial.Rule 612. As
23. 21 CFR 58 amended Mar. 2, 1987, eff. Oct. 1, 1987.