The Criminal Justice System: A Guide for Law Enforcement ... - NHTSA

Distribution - the movement of the drug throughout the body
Metabolism - the body’s way of breaking down a complex substance into smaller pieces
in an effort to get rid of it
Elimination - getting the drug or its smaller pieces out of the body through urine, feces,
sweat, saliva, or breath
PRACTICE POINT
PLAIN LANGUAGE
The polysyllabic words used in toxicology have the potential to become mind-numbing to the
non-toxicologist audience (pharmacokinetics, pharmacodynamics, epidemiological studies,
methylenedioxymethamphetamine, tetrahydrocannabinol, etc.) This is not to suggest you can
never use these words. However, when you use them, immediately explain their meanings in
common, everyday language—and then try to limit repeating the words and substitute as
much as possible common language to convey your message. Refrain from using several of
these terms within a short statement:
Scientific
Studies conducted by some of our most renowned forensic toxicologists demonstrate the
pharmacokinetics of methylenedioxymethamphetamine to be typically excreted 65%
unchanged, with the principal metabolite being methylenedioxyamphetamine. Our
epidemiological studies further show that the driving population and others are adversely
affected by ingestion of MDMA, with symptoms including ataxia and diaphoresis,
accompanied by psychomotor and memory dysfunction.
Plain Language
Scientific studies done by experts show that MDMA, a relatively common street drug—
you may have heard of it as “ecstasy”—seems to make people feel more alert, even hyper. In
reality, someone on MDMA will frequently be uncoordinated, restless, sweat heavily, have
trouble controlling their movements, and be unable to think clearly. Obviously, a person in
this condition is a risk to himself and others when driving.
Having thus painted a “word picture” of what a person on MDMA looks like, the toxicologist
can now compare the picture of this uncoordinated individual to what a person should look
and act like when driving.
The Science of Toxicology
“Alcohol is a drug, but not all drugs are alcohol.”
When testifying about the effects of alcohol and/or other drugs on a person’s
ability to drive, it will be necessary to go into some detail about the physical and mental
effects of the substance(s) involved. You may be asked about retrograde extrapolation,
zero order kinetics, first order kinetics, pharmacodynamics, and a host of other complex
(to the lay person) topics. It is safe to assume the average juror has no knowledge
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