DRE Checklist, Step 7: Dark Room Examinations
A Drug Recognition Expert (DRE) must follow a checklist that breaks down into twelve components. The next few blogs will examine each step in detail.
Step 7: Dark Room Examinations
Using a pupillometer, which is a plastic card on which a number of circles and semi- circles appear, the DRE will take the subject in to a dark room to estimate the pupil size in room light and do the following:
- The DRE will hold the pupillometer next to the subject's eye and locate the particular circle or semi-circle that is closest in size to the subject's pupil, and they will record the size of that circle or semi-circle;
- He will first do the left eye and then the right eye;
- Then he will turn off the lights in the room and wait about ninety seconds so that his eyes can adjust to the darkness;
- He will use a penlight to introduce different levels of illumination into the subject's eyes, first starting with a low level of light, enough to see the pupils and obtain an estimate of their size;
- He will then shine the light directly in to the subject's eyes and for each level of illumination, the DRE will hold the pupillometer up next to the eyes and take measurements;
- He will hold the light for fifteen seconds and then observe how quickly the pupil reacts to the direct light.
The reason it's important for a DRE to check pupil size and pupil reaction to the light is because the eyes react differently to the different drug categories. For example, narcotic analgesics will cause the pupils to become very constricted whereas hallucinogens typically cause the pupils to dilate. Also checked will be the subject's nasal area and mouth to check for any signs of ingestion in the oral and nasal area.
If you or a loved one has been charged with a DUI with drugs, call our offices today for a free consultation. Criminal Defense Attorney James N. Dicks specializes in DUI cases. As a member of The National College for DUI Defense and with over 25 years of legal experience, he can help you.
Source: A training manual for the Drug Evaluation and Classification Program
Don’t Waste Any Time!
Call us today for a FREE Consultation
(760) 630-2000


- Criminal Law Expert - Led by a Board Certified Criminal Law Specialist. Read More
- 100s of Cases Tried - Since 1990, James Dicks has represented hundreds of clients. Read Bio
- Client Approved - Read our online testimonials from satisfied jD LAW Clients. Yelp Reviews


- October 30, 2023
Working with Expert Witnesses in Defense Cases - October 20, 2023
The RICO Act: Defending Against Racketeering … - October 10, 2023
Child Pornography Charges: Legal Defenses and …