Interviewer: Have you ever re-tested someone’s blood sample?
David: Yes, there is a lab in New Hampshire that does the second sample analysis work. Generally speaking, with the marvels of technology being shown off and all the TV programs, one would think that the second sample would be identical to the digits in the government test results.
But believe it or not, there is a non-matching number in approximately 10% of all the breath tests. The second sample numbers do not necessarily come back with the same two digits. In these cases the actual number, plus or minus whatever, is going to be the difference between guilty or not guilty.
Yes, we spend the money to have the second sample tested. In a surprising number, about one in ten, the second sample number comes back different. Sometimes it is higher; sometimes lower or sometimes all screwed up.