Does s/he frequently have red or glassy eyes, or dilated or constricted pupils?
Keep in mind, DUI stands for “Driving Under the Influence” which includes alcohol and other drugs. DREs have various ways of recognizing other drug use. An easy way to spot users of some drugs is to measure pupil size. The diameter of the iris (the colored part) is about 12 millimeters (mm). The pupil (the dark part) is 2.5 to 6.5 mm in normal adults (slightly larger in children) depending on light conditions, or about 1/5 to a little over 1/2 the diameter of the iris. If it’s less than 2.5 mm, “pinpoint” sized, opiate (e.g., heroin) or non-therapeutic levels of opioid (e.g., Demerol) use is evident. There is evidence of marijuana or heavy alcohol use at 6-7 mm in light (these drugs can also cause the eyes to appear red or “glassy”.) “Does he often have red eyes, flushed face or ‘drinker’s nose’?” This affects a select few and only with certain drugs. It’s important to recognize that some addicts’ eyes never turn red, while the eyes of some non-addicts do so with as little as .04 BAC.
