Cross-Examination on Horizontal Gaze Nystagmus in a Drunk Driving Case

Attorney - Are you familiar with other causes for early nystagmus—that is, other than alcohol?
Officer - I've read something about it.

Attorney - Are you familiar with the effects of a streptococcus infection on nystagmus?
Officer - No, I'm not.

Attorney - The effects of hypertension on nystagmus?
Officer - No.

Attorney - The effects of motion sickness, such as in a car?
Officer - No.

Attorney - The effects of caffeine?
Officer - No.

Attorney - Nicotine?
Officer - No.

Attorney - Aspirin?
Officer - No, counselor, I'm not.

Attorney - Antihistamines? Depressants? Anticonvulsants?
Officer - As I said, no.

Attorney - Flu? Epilepsy? Inner ear problems?
Officer - No.

Attorney - Isn't it true, Sergeant, that these and dozens of other conditions can cause early onset of nystagmus?
Officer - I couldn't say.

Attorney - You only know about one possible cause, right? Alcohol?
Officer - Alcohol causes nystagmus,yes.

Attorney - By the way, Sergeant, was my client suffering from any of these conditions—flu, epilepsy, car sickness?
Officer - I really couldn't say.

Attorney - Had he taken any aspirin in the hours before you gave him your version of the nystagmus test?
Officer - I couldn't say.

Attorney - Had he smoked a cigarette?
Officer - As I've said, I don't really know.

Attorney - Drunk any coffee?
Officer - Counselor,I have no way of knowing.

Attorney - Sergeant, did you even bother to ask him?
Officer - Obviously not.

Attorney - Are you familiar with "circadian rhythm"?
Officer - Circadian rhythm?

Attorney - Yes.
Officer - No,I'm not.

Attorney - You are not familiar with the fact that our bodies have a "biological clock" that governs our physiological functions? A subconscious 24 hour clock that tells our bodies what to do, when it's time to sleep, that sort of thing?
Officer - Oh, yes, I've heard of that.

Attorney - Then you're aware that from midnight to 5:00 Officer - M., this circadian rhythm decreases the angle of nystagmus onset by one degree?
Officer - I was not aware of that, no.

Attorney - This would increase your reading of a person's level of intoxication, wouldn't it?
Officer - By a small amount, I suppose.

Attorney - You would think his blood-alcohol level was higher than it actually was, right?
Officer - By a small amount.

Attorney - Yet, you were not aware of this phenomenon?
Officer - Not as it related to nystagmus.

Attorney - Sergeant, do you consider yourself an expert on nystagmus?
Officer - I believe I am.

Attorney - Do you understand how it works?
Officer - You mean the physiology?

Attorney - Yes.
Officer - I can't say I do.

Attorney - Do you understand the dozens of potential causes of early nystagmus—besides alcohol?
Officer - I've already said I was not familiar with these.

Attorney - What is nystagmus, Sergeant?
Officer - What is it?

Attorney - Yes. Why does the eye react the way it does? What conditions or substances can cause it?
Officer - I couldn't say.

Attorney - Nevertheless, you consider yourself an expert?
Officer - I am qualified, yes.