TDCAA    TDCAA Community  Hop To Forum Categories  Criminal    Vertical Gaze Nystagmus
Go
New
Find
Notify
Tools
Reply
  
Vertical Gaze Nystagmus Login/Join 
Member
posted
Okay. Does anyone know of any pending cases that might get the CCA to look at the scientific basis for VGN?

Specifically, in Emerson, 880 SW2d 759 the CCA looked at the underlying science on HGN and relieved the State of having to present scientific evidence with regard to HGN testing.

Will or is VGN being considered by the CCA?
 
Posts: 956 | Location: Cherokee County, Rusk, Tx | Registered: July 11, 2001Reply With QuoteReport This Post
Member
posted Hide Post
If someone is going to utilize the presence of vertical nystagmus as an indication of criminal activity, I would be surprised if there is any scientific basis. Only certain anticonvulsant drugs have been shown to induce vertical nystagmus. I believe it is a myth that the presence of vertical nystagmus without HGN indicates the recent consumption of narcotic drugs. The State was unable to muster any scientific evidence in Stovall, 140 S.W.3d 712.
 
Posts: 2386 | Registered: February 07, 2001Reply With QuoteReport This Post
Member
posted Hide Post
There was HGN in my case. And Stovall was the prompt for the post.
 
Posts: 956 | Location: Cherokee County, Rusk, Tx | Registered: July 11, 2001Reply With QuoteReport This Post
Member
posted Hide Post
Martin, you might want to notify the National Highway Traffic Safety Administration about your views. According to one APRI monograph, the NHTSA has added VGN to the FST's approved for officers.

For more info, read this article.
 
Posts: 7860 | Location: Georgetown, Texas | Registered: January 25, 2001Reply With QuoteReport This Post
Member
posted Hide Post
John, I did not read anything in either article to support the idea that VGN is a reliable indicator of use of narcotic drugs, though there is some mention of a correlation of some type. Use of VGN to indicate a high level of alcohol consumption is a different story. Clearly there are studies to support the use of a VGN test along with HGN in the SFST. My problem has been that officers seem to be taught that presence of vertical nystagmus alone (when HGN is not observed) translates to an indicator of drug use. I fail to find it as part of a DRE protocol, and the literature I have read not only does not support that theory, but discounts the claim. I actually hope there is something more out there on the subject. But, I am still looking.
 
Posts: 2386 | Registered: February 07, 2001Reply With QuoteReport This Post
Member
posted Hide Post
"If someone is going to utilize the presence of vertical nystagmus as an indication of criminal activity, I would be surprised if there is any scientific basis." - Martin Peterson

I was responding to your above statement. Although your subsequent sentences might have narrowed that thought, I didn't get it and was concerned that our average reader would think you were applying that statement to any use of VGN. It wasn't clear to me that you were only applying it to detection of drugs in suspects and NOT to the detection of alcohol.

So, you agree is it acceptable for alcohol?

As for the initial posting, I would think someone needs to do a good hearing and acceptance of VGN. So, are there any appellate lawyers out there working up a reply brief on the issue?
 
Posts: 7860 | Location: Georgetown, Texas | Registered: January 25, 2001Reply With QuoteReport This Post
Member
posted Hide Post
The brief I am working on falls between Quinney andStovall. Oral arguments have been requested. Depending on the outcome at COA, we might have an issue for review.
 
Posts: 956 | Location: Cherokee County, Rusk, Tx | Registered: July 11, 2001Reply With QuoteReport This Post
Member
posted Hide Post
If an officer tells you he saw VGN and no HGN, then he is mistaken. It is quite possible that you will see HGN and no VGN, but it is impossible to see VGN and not see HGN first.

We teach officers that the drugs that cause HGN (depressants, inhalants, and PCP) are the same drugs that cause VGN. VGN is a indicator that the person has consumed a high dose of alcohol for that person, or they have used an inhalant or PCP.
 
Posts: 151 | Location: Fort Worth, Texas | Registered: February 14, 2001Reply With QuoteReport This Post
  Powered by Social Strata  
 

TDCAA    TDCAA Community  Hop To Forum Categories  Criminal    Vertical Gaze Nystagmus

© TDCAA, 2001. All Rights Reserved.