The cops will say no. Truth is that there has not been any scientific studies done to verify that HGN would not be effected. The cops will say that visual acuity is not needed for the test, thus taking off glasses is alright. But, when one eye can't see something clearly, the body compensates by shifting the other eye as the one to observe. This very well may make the eyes appear to jerk, which the cop will testify that shows alcohol level. The test was never designed to test for impairment, only to determine a statistical probability of an alcohol level over .10. Speaking of validation, the standardized field sobriety tests were never submitted to any publication for peer review to establish that scientific standards were met.
As Mr. Rudes stated, there was not scientific research conducted to determine if it would a stigmatism would affect HGN.
Though I can tell you, as a former DUI TOP COP, I would not have known whether it would have affected the HGN or not. And, I can assure you that no other DUI TOP COP's or DUI wannabe cops would have a clue.
But, you raise a valid point that could be used as a Defense to the HGN. And, all it takes is reasonable doubt. A learned OVI Defense Attorney may be able to use that defense to help suppress evidence, or get the DUI tossed out. BUT, you need to make sure that you contact an OVI ( DUI ) Attorney. There is a difference.
Attorney Mark A. Deters
Deters Law LLC
(937) 224-1100 - southern Ohio
(419) 466-8925 - northern Ohio
You should post this question to an ophthalmologist.
This answer is my personal opinion, offered for informational purposes only. It is not a legal opinion, nor is it legal advice, nor does it create an attorney-client relationship with anyone reading it.
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