Opinion - The continuing battle between prosecutors and defense attorneys in DUI trials is similar in many ways to the old arms race between the United States and the old Soviet Union. As one side develops a new "attack" strategy, the other side develops a new "defense".
Sometimes the government wins, sometimes the defense wins.
Each side gains a better understanding of the legal and scientific aspects of DUI cases. The end result is that the government is encouraged to do a better job, investigating, documenting, and prosecuting DUI cases. As the government does their job better, the likelihood of a guilty person "getting off" of a DUI charge lowers significantly.
In the few years I've been available to the defense community as an independent criminalist, I've seen improvement in the way officers investigate DUI cases, document DUI investigations, crime labs carry out analysis, and prosecutor's conduct cases.
After a seminar I gave on blood alcohol analysis, I was approached by an employee of the Arizona Department of Public Safety Crime Lab. They told me I made some valid points in my presentation. Within a few months that lab had instituted new changes, to improve the quality of their analysis.
Another laboratory has purchased new equipment, when old equipment couldn't adequately be shown to be contaminant free.
One law enforcement agency now properly handles blood draw samples, to help ensure the integrity of the evidence.
Officers have approached me during trial breaks to clarify points I made during testimony about misunderstandings the officer had about field sobriety testing.
Common terms incorrectly used during testimony as being phased out for more accurate terms.
It's interesting to note that my work as an independent criminalist has had a greater effect in improving the quality of DUI investigation in Arizona, than when I worked for the government.
About the author: Erik Brown is a forensic scientist who frequently testifies and consults about DUI blood and breath testing, field sobriety testing and gives expert opinions in court. He is the author of the forensics blog, Benchnotes.
