Is a learned treatise of how alcohol affects the defendant's mental and physical faculties admissible if refered to in the Officer's testimony, and the Officer is not considered an expert witness, under the Rules of Evidence.

No. The first line of 803(18) limits the exception to an expert. Now, your officer is likely an expert on HGN. Is there anything he/she could pull out of the treatise relevant to HGN and loss of faculties?

Thanks for the reply!!! This is my first time to use the User Forum. I had been looking at R.Evid. 803(18) but was not sure how to use it without an expert.

I love your idea about getting the information in through the Officer as an HGN expert.

Right now all I have is a toxicology report of how alcohol affects the mental and physical faculties. But I believe that an HGN learned treatise would have the same information.
Do you have any sourses that I can contact?

Thanks again,
Melissa Daylong
Asst. County Attorney
Aransas County (Rockport)

How about the NHTSA Manual? Some judges will allow testimony equating HGN results with a BAC of over a .08, as referenced in the NHTSA manual studies, and other judges won't. Ask others in your office about your judge. A 2006 NHTSA Student Manual is available as a PDF under "DWI Resources" on the TDCAA main page....

Read Emerson v. State, 880/759. I do not believe that you can quantify BAC results with a HGN test.

I know you folks are talking about what the law will allow, but you might want to consider the following as a practical issue: The accuracy of predicting whether a BAC is above or below 0.08% by an SFST depends on what the BAC actually is. There is a published study that indicates that if a BAC is below 0.04% an officer is about 80% accurate in determining that the individual was greater than or less than 0.08% by SFST, and if the BAC is greater than 0.09% the officer is about 90% accurate in determining that the individual was greater than or less than 0.08% by SFST. However at BAC 0.06 to 0.08% the accuracy in determining if a person is above or below 0.08% is about 30 - 60%.* Just thought you may want the "heads up" on this study in case you face it in court.

*J Forensic Sci, May 2005, Vol 50, No. 3 pp 662-669

Take blood.