By Aaron Botts
One of the most interesting moments from my recent presentation with Brad Owens of the Georgia Public Safety Training Center at the 2026 IACP IDTS Conference, Ancient Secrets of Southern California, had nothing to do with a statistic on a PowerPoint slide.
I asked the room a simple question:
“How many of you have actually read all six of the studies presented in the SFST program?”
In a room of roughly 250 people, fewer than five hands went up.
This was not intended to be a “gotcha” question. In fact, it became one of my favorite teaching moments of the presentation.
Most SFST instructors are familiar with what the curriculum tells us about the studies. We know the major findings, validation percentages, and conclusions that made their way into our manuals. But there is a tremendous amount of context buried in the original research that never makes it onto the PowerPoint slides.
Knowing the lesson plan is only the beginning
After the presentation, an attendee told me he had been a DRE Instructor for more than a decade but had never actually sat down and read the original SFST studies.
I appreciated his candor because I suspect his experience is far more common than those five raised hands suggested.
When you become an instructor, knowing the lesson plan is just the beginning. Our students deserve instructors who understand not only what we teach, but why we teach it.
The curriculum does an excellent job of turning an enormous amount of information into something we can teach efficiently. The three foundational Southern California Research Institute reports from 1977, 1981, and 1983 alone total approximately 236 pages of research. In the SFST curriculum, that history and research must be condensed into just a handful of slides because of the purpose and limitations of the course.
A basic SFST student does not need a multi-hour lecture on research design, statistical analysis, or every psychophysical test researchers considered. But instructors should know that information exists and occasionally go looking for it.
The manual tells you what. The research tells you why.
Take the original 1977 research.
The curriculum tells us that six tests were evaluated: One Leg Stand, Finger-to-Nose, Finger Count, Walk and Turn, Tracing, and Nystagmus.
Researchers actually considered 16 different tests before narrowing their focus. The six tests ultimately evaluated were found to be alcohol-sensitive, and researchers selected the three they believed performed best.
Another detail I particularly like as an instructor and witness is that some drinking participants were also evaluated using a driving simulator. That provides a direct connection among alcohol concentration, psychophysical test performance, and actual driving ability.
That is useful information when a student or juror asks:
“But what does standing on one leg have to do with driving?”
Now you can explain some of the research foundation underneath the answer.
Sometimes the “why” is hiding in one sentence
The 1981 study provides another great example.
Have you ever had a student ask why we put a subject in that awkward heel-to-toe starting position during the Walk and Turn?
During development of the test, LAPD officers added the starting position, and researchers found it increased the test’s sensitivity to impairment.
That one piece of information changes how I teach it.
It is no longer simply, “Stand like this because that is how the standardized test is administered.” Now I can explain that the position itself is part of the divided attention task and was added because it helped researchers better detect impairment.
That explanation takes only another 20 seconds in class, but it gives the student a reason to care about administering the test correctly.
Context matters when we quote validation numbers
Consider the 1997 Florida Validation Study. The officers were not randomly selected patrol officers who had just completed basic SFST training. The study used eight deputies from the Pinellas County Sheriff’s Office Selective Traffic Enforcement Program. All were DUI or DRE instructors, had more than six years of experience, had made at least 200 DUI arrests, and received an SFST refresher before the study.
Those officers correctly made 95 percent of arrest decisions and 82 percent of release decisions for drivers with measured BAC results.
That shows that training matters, experience matters, continuing practice matters, and standardization matters.
If we quote a validation percentage without understanding who produced it and under what conditions, we know the number. If we read the study, we understand what the number is actually telling us.
You do not need to become a research scientist
I am not suggesting that every SFST Instructor needs to memorize hundreds of pages of research, understand every statistical calculation, or turn a basic SFST class into a graduate-level research seminar.
I am suggesting that instructors occasionally go one level deeper than the material we expect our students to know.
Read the original study and highlight something that surprises you. Compare what the researchers wrote with what appears in the current manual. Look up a term you do not understand. Ask another instructor what he or she thinks. If something still does not make sense, reach out to someone who knows more than you do.
Then bring the useful pieces back to your classroom.
Be ready for the best question a student can ask
Eventually, a good student is going to ask:
“Why?”
Why do we use these three tests?
Why do I have to hold the stimulus that distance from the face?
Why does the Walk and Turn start in that position?
Why are those behaviors considered clues?
Why should I trust these tests?
Sometimes, “because that is the standardized procedure” is the correct answer. Standardization matters.
But a good instructor should also understand how that standardized procedure came to exist.
You do not need to know every answer immediately. I certainly don’t. But when you do not know, that question should become homework for the instructor too.
The truth may be in the appendices
Brad Owens and I spent a lot of time digging through these studies while developing Ancient Secrets of Southern California. The more we read, the more we realized how much useful information never makes it into an ordinary SFST class.
That reinforced something I have believed for a long time: teaching the slide is easy. Understanding the foundation underneath the slide takes more work.
Our students deserve instructors willing to do that work.
You do not need a PhD or to memorize 236 pages of research. But if you teach SFSTs, take some time to read the studies that created the program you are teaching.
The manual tells us what survived the research.
The research tells us why.
And sometimes, the truth really is buried in the appendices.
