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Is a horizontal gaze nystagmus test valid for sobriety testing if I have unequal pupils?

Pasadena, CA |

I was recently arrested for a DUI in California. I was pulled over for speeding and the officer administered the horizonal gaze nystagmus test. I refused all other field sobriety testing but did submit to a breathalyzer at the police station (.11). Since then, I have done research on the HGN test and according to the NHTSA article I found, the officer is supposed to check for equal pupil size and discontinue testing if pupils are not equal. I naturally have one pupil that is bigger than the other (my ophthalmology records mention this). So is the HGN test valid if the officer failed to note this? Can the argument be made that if the officer failed to note something so basic that he can't be expected to correctly note the nystagmus?

Attorney Answers 3


  1. the other thing that you would want to consider is that particular cast make a show the presence of alcohol or drugs but does not show the level or BAC.

    what is a means is is you can exhibit signs of horizontal gaze nystagmus amd be .03 .04 or even .05
    well under the legal limit it is not really an effective test in finnding out whether or not you are over the limit

    you should really consult with an attorney on this


  2. It is definitely something that will work in your favor. Most officers are trained to "take it into consideration", but never trained on how to do that. As a standardized test, there is no uniform way for an officer to consider naturally inequal pupils so is definitely something that should be further explored with your attorney. You should get certified copies of this documents (optomologist docs) that show this occurence in your eyes.

    Look for a DUI attorney in the area to help you out. The DA will consider this as part of the negotiation, you will likely need to get an expert for the DMV hearing though. Better to let your attorney handle that, instead of you simply making the argument since your are likely not an optomologist or expert on FSTs, so your argument alone will hold no weight.

    Feel free to call me if you want to discuss further.

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  3. You are absolutely correct. Unequal pupils should be the end of the HGN "exam" in this scenario. A vigorous cross examination of the arresting officer should point this out and, quite frankly, be quite enjoyable for your defense attorney. However, you will not get anywhere without competent counsel. There are many great lawyers here on Avvo. Most will offer a free consult. Call a few.

    Best of luck to you.

    John Buckley

    No answer here should be considered to form an attorney-client relationship. You should consult with a licensed attorney in your jurisdiction so that a full evaluation of the facts of your case can be conducted.