Arrested for DUI and officer failed to record the audio on the dash cam while conducting field sobriety test. Admissible?

What audio was left out that matters? What parts of the conversation or comments do you believe need to be heard? it is audio that says you were not driving? Regardless, the video is still admissible without the audio. It is probably not worth fighting. Remember, your attorney's credibility with the judge and the DA, and thus the strength of your defense and your ability to plea bargain or reach a good disposition, is paramount in all cases. Pick your battles.

I am currently litigating this very issue in Los Angeles County. If we can show a pattern, that the cops are doing this on purpose, it could expose them to sanctions for intentionally destroying evidence. Call some lawyers for a free consultation ASAP!!!!

It all depends on what the audio could challenge or dispute and as my colleagues have opined, if there is some type of pattern of conduct to not turn on audio if audio use is part of the standard practices and procedures for the department. Many departments including CHP require the use of personal audio devices, yet for some reason or another, the mics are not turned on. The audio becomes important when there is a dispute regarding slurred speech or what someone said that is material to the case. Consult an experienced DUI attorney in the are where the arrest occurred. Good Luck!

Probably admissible unless you can show that there was some deliberate or malicious attempt to destroy evidence that might prove your innocence.

Yes, admissible. No legal issue. No legal duty to record. Look to other defenses.

As Mr. Slaten pointed out - if you can show a pattern, then you might be able to keep the video out. Otherwise, it is almost definitely going to be admissible (by either party) as it does not run afoul of any U.S. constitutional guarantee. Of course, a video with no audio raises more questions than it answers in the eyes of a jury. (But, you have to get to a jury first.) If there are videos with audio from the same vehicle on the same evening - even better. Jurors don't like "drunks," but they like crooked cops even less. Your attorney has some digging to do re other videos from that evening. Then, with that in hand, you may have some material to leverage to bring about the best possible outcome in your case. Good luck!