"Rhode Island Breathalizer Issues"
11/08/2011 06:52 AM Categories: Breath Test | Breathalizer | Rhode Island | Attorney | Cross Examination
Cross-examination of the prosecution expert can make a point to the jury that the defendant's rights should not be determined by small samples and breath-alcohol measurements involving miniscule quantities. The cross-examiner could probably get an admission from the expert that, if the amount of alcohol involved in a particular test were on a table in front of the jury, they could not see, smell, taste, or feel it. However, it would probably do the cross-examiner no good to push the expert too far on the matter of minute quantities since, given an opportunity, the expert would point out that making measurements of small quantities is not uncommon with modern laboratory procedures. Cross-examination of the expert to emphasize to the jury the opportunity for error in measuring extremely minute quantities of breath-alcohol might run as follows: ...
Q. Breath analysis for alcohol amounts to this, doesn't it: a breath-test device collects a certain amount of air exhaled from the subject's lungs and passes that air through the chemicals in a test ampoule; the chemicals gather the alcohol out of the sample; and the device measures the alcohol absorbed by the chemicals.
A. That is right.
Q. Any claim to accuracy made for breath-testing devices assumes that the procedure measures almost infinitesimal quantities of alcohol found in the breath, is that correct?
A. Yes.
Q. As I understand it, a Breathalyzer collects the equivalent of 52.5 cubic centimeters of breath, is that correct?
A. That is correct.
Q. How many cubic inches does 52.5 cubic centimeters amount to?
A. A little more than 3 cubic inches.
Q. And the breath-alcohol reading is converted by the testing device into a blood-alcohol reading?
A. Yes.
Q. You have testified to a blood-alcohol reading of the defendant's breath sample taken on , of 0.15 percent, is that correct?
A. Yes.
Q. A reading of 0.15 percent blood-alcohol presumes to indicate that in the defendant's blood there were 15 parts by weight of alcohol in every 10,000 parts of blood, is that correct?
A. That is correct.
Q. And since the specific gravity of alcohol is quite close to four-fifths that of whole blood, that same concentration would amount to only two parts of alcohol by volume in every 1000 parts of the defendant's blood, is that correct?
A. Yes.
Q. However, it was the defendant's breath that was tested and not his blood?
A. Yes.
Q. And breath tests for alcohol are not as precise as blood tests for alcohol, is that correct?
A. Yes.
Q. Hasn't the alleged relationship between breath-alcohol and blood-alcohol been stated in fixed terms, presumably applying to all persons?
A. Yes.
Q. What is that relationship?
A. It is 1:2100. Blood-alcohol is 2100 times greater than breath-alcohol in a given subject.
Q. However, aren't there individuals in whom the relationship varies from the average?
A. Yes.
Q. If we accept, just for the moment, a breath-alcohol to blood-alcohol ratio of 1:2100, the quantity of alcohol measured in the breath sample would be equal to the quantity of alcohol to be found in 1/40th of a cubic centimeter of the defendant's blood?
A. That is correct.
Q. Is it true that one cubic centimeter of a liquid such as blood is equivalent to 0.034 fluid ounces, or very close to 1/30th part of an ounce?
A. That is correct.
Q. So, then, the amount of alcohol in the breath sample collected from the defendant would be equivalent to the amount we would expect to find in 1/30th part of 1/40th part of an ounce, 1/1200th part of an ounce, or 0.00085 ounce of his blood?
A. Yes.
Q. To pin these extremely small amounts down further, since there are 480 drops in an ounce by apothecaries' fluid measure, the equivalent in blood of the amount of breath analyzed is less than half a drop—amounting, as a matter of fact, to 408/1000ths of a drop?
A. That is correct.
Q. And the amount of alcohol gathered by the chemicals to produce a blood-alcohol reading of 0.15 percent would be equivalent to only 2/1000ths of that half drop of blood, or eight ten-thousandths of a drop, or five hundred-thousandths of a cubic centimeter, or seventeen ten-millionths of an ounce?
A. I assume you are correct.
Q. Breath analysis for alcohol amounts to this, doesn't it: a breath-test device collects a certain amount of air exhaled from the subject's lungs and passes that air through the chemicals in a test ampoule; the chemicals gather the alcohol out of the sample; and the device measures the alcohol absorbed by the chemicals.
A. That is right.
Q. Any claim to accuracy made for breath-testing devices assumes that the procedure measures almost infinitesimal quantities of alcohol found in the breath, is that correct?
A. Yes.
Q. As I understand it, a Breathalyzer collects the equivalent of 52.5 cubic centimeters of breath, is that correct?
A. That is correct.
Q. How many cubic inches does 52.5 cubic centimeters amount to?
A. A little more than 3 cubic inches.
Q. And the breath-alcohol reading is converted by the testing device into a blood-alcohol reading?
A. Yes.
Q. You have testified to a blood-alcohol reading of the defendant's breath sample taken on , of 0.15 percent, is that correct?
A. Yes.
Q. A reading of 0.15 percent blood-alcohol presumes to indicate that in the defendant's blood there were 15 parts by weight of alcohol in every 10,000 parts of blood, is that correct?
A. That is correct.
Q. And since the specific gravity of alcohol is quite close to four-fifths that of whole blood, that same concentration would amount to only two parts of alcohol by volume in every 1000 parts of the defendant's blood, is that correct?
A. Yes.
Q. However, it was the defendant's breath that was tested and not his blood?
A. Yes.
Q. And breath tests for alcohol are not as precise as blood tests for alcohol, is that correct?
A. Yes.
Q. Hasn't the alleged relationship between breath-alcohol and blood-alcohol been stated in fixed terms, presumably applying to all persons?
A. Yes.
Q. What is that relationship?
A. It is 1:2100. Blood-alcohol is 2100 times greater than breath-alcohol in a given subject.
Q. However, aren't there individuals in whom the relationship varies from the average?
A. Yes.
Q. If we accept, just for the moment, a breath-alcohol to blood-alcohol ratio of 1:2100, the quantity of alcohol measured in the breath sample would be equal to the quantity of alcohol to be found in 1/40th of a cubic centimeter of the defendant's blood?
A. That is correct.
Q. Is it true that one cubic centimeter of a liquid such as blood is equivalent to 0.034 fluid ounces, or very close to 1/30th part of an ounce?
A. That is correct.
Q. So, then, the amount of alcohol in the breath sample collected from the defendant would be equivalent to the amount we would expect to find in 1/30th part of 1/40th part of an ounce, 1/1200th part of an ounce, or 0.00085 ounce of his blood?
A. Yes.
Q. To pin these extremely small amounts down further, since there are 480 drops in an ounce by apothecaries' fluid measure, the equivalent in blood of the amount of breath analyzed is less than half a drop—amounting, as a matter of fact, to 408/1000ths of a drop?
A. That is correct.
Q. And the amount of alcohol gathered by the chemicals to produce a blood-alcohol reading of 0.15 percent would be equivalent to only 2/1000ths of that half drop of blood, or eight ten-thousandths of a drop, or five hundred-thousandths of a cubic centimeter, or seventeen ten-millionths of an ounce?
A. I assume you are correct.