Monday, July 2, 2018

How reliable are DWI blood test results? Well, it depends . . .

In a recent DWI prosecution, ETKS associate Paul Meabon moved to preclude the introduction of the results of a sample taken by a registered nurse at the direction of a Rochester Police officer pursuant to Vehicle and Traffic Law § 1194(4)(a)(1)(I), which provides, in relevant part that “[a]t a police officer’s request … a physician, a registered professional nurse, a registered physician assistant, a certified nurse practitioner, or an advanced emergency medical technician as certified by the department of health” may withdraw blood to determine the blood’s alcoholic or drug content.
Mr. Meabon argued that because the discovery provided revealed that the sample had not been properly collected or stored, any test results relating to that sample would unreliable and therefore irrelevant.
In New York, a blood draw must be “safe, reliable” and “impose no more physical discomfort than is reasonably necessary” (Matter of Abe A., 56 NY2d 288, 297-98 [1982]). Reliable methods fall within “accepted medical standards” including, for example, the application of an “aqueous solution of a nonvolatile antiseptic” on the area of skin where blood is drawn (see id., referencing Schmerber v California, 384 US 757, 771-772 [1966]; 10 NYCRR 59.2[d]). A blood sample collected outside statutory guidelines must be suppressed (see People v Olmstead, 233 AD2d 837 [4th Dept 1996]; People v Ebner, 195 AD2d 1006, 1007 [4th Dept 1993]).
Along with the method of its collection, a blood sample’s reliability depends on the sample’s storage. In Mr. Meabon’s case, the nurse stored each blood sample in a NIK Public Safety, Inc. vacutainer tube containing chemicals to safeguard the sample’s integrity.
One chemical contained in the tube, 20 milligrams of potassium oxalate, is a powdered anticoagulant that hinders blood’s production of thrombin, an enzyme that stimulates clotting (Peter Gerstenzang & Eric H. Sills, Handling the DWI Case in New York § 38:10 [2015-2016 ed.]; see 10 NYCRR § 59.2[c][4][ii] [“blood shall be deposited in a clean container containing a solid anticoagulant”]). Clotting in a blood sample concentrates alcohol in the sample’s liquid, the portion tested to determine blood alcohol content, causing an erroneously high result (see People v Boyst, 177 AD2d 962 [4th Dept 1991] [blood sample without anticoagulant admissible given laboratory’s use of clotting conversion factor]).
A second chemical, sodium fluoride, is a preservative staving off fermentation as a sample decays (Handling the DWI Case in New York, supra at § 38.11). A blood sample without a preservative ferments during storage (even while refrigerated) and, in some cases, raises a sample’s alcohol content 0.25% or higher (id.).
Some careful attention to a critical variance between the instructions for the blood draw kit and the procedures followed presented an issue.
Because clotting and fermentation undermine a blood sample’s test results, the blood draw kit used instructs the nurse to “slowly invert the tubes at least five times immediately after blood collection” (see id. at § 38:8). Likewise, the kit instructs the officer supervising the blood draw, to “INVERT [the tube] slowly and completely at least 20 times” to “ensure proper mixing with the anticoagulant powder” (see id.)
In Mr. Meabon’s case, however, neither the nurse nor officer inverted the tubes as directed before sealing the tubes in the kit’s mailer box. As a consequence, the anticoagulant and blood were not properly mixed and the blood could have clotted before testing. From the test results provided, it was unclear whether the testing laboratory factored clotting into the test results (see Boyst, supra). Furthermore, the test results provided failed to indicate how the laboratory stored the tubes, whether the tubes contained sodium fluoride, or whether any preservative worked to stave off fermentation during the blood sample’s pre-testing decay.
Some issues to consider in your next blood draw DWI case.

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