Blood Alcohol Concentration (BAC)
Calculations
Download EZ-ALC Blood Alcohol Chart Software
Click here to download EZ-ALC
When you click on the link above to download
EZ-ALC, your web browser will ask you where you
want to save EZALCSW.EXE. Put it somewhere
you'll remember!
After it's done downloading, use the
"Run" command to run the file and it
will automatically install on your computer,
with an icon on the desktop, and another one in
"Programs" on your "Start"
menu. If you don't want the desktop icon, just
click on it once, then right-click and select
delete from the pop-up menu.
Fast Eddie's Simple 8/10 Method for Hand Calculating BAC
Click here
for an article on how to use Fast Eddie's
Simple 8/10 Method (Widmark's formula).
Why Do BAC Calculations From Drink
History?
It's possible to use "Widmark's Formula" to
calculate a Blood Alcohol Concentration (B.A.C.) based
upon known factors about a person, including their
weight, gender, and what amount of alcohol they
consumed.
It's plain that the defense will want to present expert
testimony on this subject to show that the B.A.C. was
below the legal limit (Veh. C. §§ 23152(b) and 23155)
at the time of driving.
Another Reason For Such
Evidence
The defendant has often admitted at the time of
arrest, consuming some amount of alcohol prior
to driving. Prosecutors often use such
statements to impeach the defendant's
credibility. They have the prosecution expert
testify as to how much alcohol the defendant
had in him at the time of his blood, breath or
urine test. Then they have their expert state
how many "drinks" the test result
means the defendant had to have consumed. The
answer usually makes the client look like a
liar. And the jury is told that they can't
trust anything the client said, like, when he
said he was not affected by the alcohol. But
your expert can often reconcile the chemical
test result with your client's admissions. The
defendant's credibility is thereby restored,
not only with regard to what he drank, but on
everything else in his testimony.
Thus, Widmark calculations can be essential not
only to showing that the defendant's alcohol
level at the time of arrest was below the legal
limit, but also to showing that the defendant
is not a liar.
There is an excellent discussion of how to use
the EZ-ALC software in court in, Fitzgerald,
Edward F., Chapter 12 "Use of the EZ-ALC
Computer Program by Attorneys and
Experts", in {NEED LINK} Intoxication
Test Evidence, 2d ed. (Deerfield,
IL: Clark-Boardman-Callaghan, 1995).
Whether you or your expert use the hand or
computer calculation method it will be
necessary for your expert to testify as to the
results.
If the calculations have been done by computer
your expert can state that he relied upon the
statements of EZ-ALC's technical consultant,
Randall C. Baselt, Ph.D., for his opinion that
EZ-ALC correctly uses Widmark's formula and is
scientifically valid. This is no different than
an expert testifying that he believes his hand
held calculator correctly adds, subtracts,
multiplies and divides, based upon the
manufacturer's representations that it does
that. The program comes with a complete
description of how it operates, along with a
copy of Dr. Baselt's extensive curriculum
vitae, showing him to be a leading authority on
the subject.
It is not necessary to show that the computer
was functioning properly or that the software
was working the way it was supposed to (People
v. Lugashi (1988) 205 CA3d 632, 252 CR 434 -
Case contains an extensive collection of
authorities on the subject). For what may be a
contrary view see Snyder, R., Assuring the
Competency of Computer Generated Evidence (No.
1, Winter, 1989) 9 Computer/Law J. 103-121.
See also State v. Pressnall 804 P2d 936 (Idaho
CtApp 1991) - Blood Alcohol Concentration
(B.A.C.) calculations based upon Widmark
formula admissible to rebut Breath Alcohol
Concentration (Br.A.C.) evidence; Tarantino,
J.A., "Using Computer Generated
Simulations in Alcohol Related Trials",
DWI Journal, 6 No. 8, Aug. 1991 (Fanwood, NJ:
Whitaker Newsletters) 1.
