In San Diego DUI trials, the Prosecution ultimately
marches in their paid laboratory person to "assume"
what the San Diego DUI driver's BAC allegedly is.
San Diego DUI defense attorneys readily wait their turn.
In each case, a San Diego DUI prosecutor first asks the
"state's expert" to answer the following hypothetical
question(s):
Q. How many drinks would be in the San Diego driver's system
at the time of the test, in order to reach a (insert BAC
number) as was obtained on the San Diego DUI breath test
machine?
or
Q. How many drinks would a (insert San Diego driver's
weight and sex) person have to consume between (insert
start drinking time) and (insert end drinking time)
in order to obtain a reading of (insert BAC # Prosecution
wishes to contend) on the (insert San Diego DUI
breath test machine - the Intoxilyzer or Intoximeter)?
The San Diego DUI prosecutor is introducing evidence with
numerous assumptions.
It would be a Denial of Due Process and the Right to Confrontation
to deny a San Diego DUI criminal defense attorney's turn
to have an opportunity to then materially cross-examine
the witness, as follows:
Mr./Ms. Prosecution lab person, please identify every assumption
that you needed to make in order to make the calculation
that gave you the specified number of drinks as the answer
to the San Diego DUI Prosecutor's hypothetical question:
Did you assume an average size
drink?
Did you assume an average human
absorption amount?
Did you assume an average human
absorption time?
Did you assume an average human
burn-off rate?
Did your answer assume a true BAC or
blood alcohol level?
Is it true there is established science correlating
levels of impairment to blood alcohol levels?
Is it true there is no such similar science correlating
levels of impairment to breath alcohol levels
(especially on San Diego DUI breath machines that do not
have
the ability to distinguish mouth alcohol from
deep lung alcohol)?
Is it true you had to therefore assume
an average conversion rate
between the amount of alcohol contained in venous blood
and the
corresponding amount of alcohol that should theoretically
be contained in a
deep lung sample of breath?
So, the assumption for average drink size has a range?
So, the assumption for average absorption rate has a range?
So, the assumption for average burn off rate has a range?
So, the assumption for average absorption time has a range?
If your assumption for the drink size were to change
value, your answer would change.
If your assumption for average absorption rate were to
change value, your answer would change.
If your assumption for average burn off rate were to change
value, your answer would change.
If your assumption for average absorption time were to
change value, your answer would change.
If your assumption as to the conversion rate were to
change value, that would also change your answer.
Of all the assumptions you made, the most highly-changing
or volatile assumption is the conversion rate.
The conversion rate changes between the amount of alcohol
contained in venous blood and the corresponding
amount of alcohol that is contained in a deep lung sample
of breath.
This means any San Diego DUI breath machine BAC reading
must have a possible range of actual blood alcohol level
results.
A San Diego DUI defense lawyer can therefore show why
it is not a good idea to "ASSUME" when trying
to determine one's true BAC.
Assuming through averages does not necessarily amount
to proof of true BAC beyond a reasonable doubt.
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