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Explaining HGN at Trial

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https://tdcaa.infopop.net/eve/forums/a/tpc/f/157098965/m/1973024596

January 28, 2003, 13:20
KMiller
Explaining HGN at Trial
We have recently received a copy of the training video DPS uses to train officers on the HGN test. We would like to use the part of the tape which shows the difference in the HGN test on a sober person vs. an intoxicated person. I understand that there are some offices which currently use this type of video at trial and I am wondering how they were able to get the judge to allow its use. Suggestions?
January 28, 2003, 23:57
WDiepraam
The tapes have been used in Harris County with some success depending on the judge's understanding of the law on "demonstrative evidence." The tape is not much different than using a demonstrative firearm in an aggravated robbery case. I suggest using it with your judges that are more apt to allow creativity and then the other judges. You can inform the latter that it is commonly accepted by ....

The first step that is used in the process is to show the officer the tape before trial so that the officer can testify that he / she is familiar with its contents. The officer should also be familiar with HGN, what causes it, and what does not cause it.

Second, have the officer go over the standard predicate regarding the admissibility of the HGN. After that is complete, have the officer discuss what HGN is and how the tape would be helpful to the jury to understand HGN, what an officer is looking for, and what an officer sees. This should be accompanied with the predicate for the admissibility of the tape.

Lastly, after completing all the above steps, make sure that it is clear that the defendant exhibited the exact same symptoms as shown on the tape, but make it is just as clear that this is not the tape of the defendant. Tell the judge that the tape is being offered purely for demonstrative purposes to assist the jury in understanding the HGN. Remember the cardinal rule that if you can talk about it, you can show a visual.

Good luck.
February 26, 2003, 10:05
Martha W. Warner
Thank you! It worked great with an uncooperative Def, no intoxilizer results and an exculpatory video. I will never try another felony DWI wothout using it!!!!!! Smile
March 03, 2003, 12:56
Neel McDonald
Where can I get me one o' them tapes? Is there a particular contact in Austin @ DPS?