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5. 15-Minute Observation & The Breath Machine

Title 17

Napa County law enforcement testing of your alcohol levels must comply with state rules (called "Title 17") which legitimize a non-doctor (in other words, your arresting officer, lab technicians, etc) engaging medical procedures to determine the amount of alcohol in your body. Your Napa DUI attorney will explain to you that in order for test results to be valid in Napa County court or at the Napa DMV, certain procedural rules must be followed. You can see these rules by clicking here: Title 17 Rules (2018) or here for the earlier 2010 version. The burden is on the police and the government to show this fundamental compliance.

Mouth Alcohol and the 15-Minute Rule

Blowing into a breath alcohol machineIn breath testing cases, one of these procedural rules is that you must be continuously observed by Napa County law enforcement for 15 minutes immediately prior to the test being taken to ensure that you did not belch, regurgitate, eat or drink, or otherwise have mouth alcohol or other foreign substances present which would cause the tests to produce falsely high results. Good Napa County DUI lawyers will examine the listed times for breath results in comparison to the time listed on the DUI arrest report for the officer's first observations of you. The best defense here is when the Napa officer arrives at an identified time prior to the DUI arrest and your Napa DUI lawyer can prove that the relevant breath tests are administered to you prior to the end of the 15-minute waiting period.

The Breath Machine

There are additional regulations in Title 17 which require that Napa County breath machines are approved devices, and calibrated at regular intervals and test within certain acceptable ranges of accuracy. Your Napa DUI attorney can subpoena and review calibration and maintenance records from the arresting agency in Napa County, and from the Santa Rosa lab of the Department of Justice, for possible defenses, particularly if your test results are relatively low.

Napa DUI lawyers see many Napa police agencies and Napa County law enforcement using a type of breath machine called the Alcotest 7410, which can be manipulated by the officer administering the test. See the California Attorney General's 7410 Information Bulletin. The YouTube video link provided below effectively demonstrates this vulnerability in the reliability of the machine, and therefore demonstrates a defense in the right circumstances, typically if there is additional evidence of sobriety, police foul play or other error during your DUI arrest. Click here to watch the demonstration (although this video effectively portrays the machine's defect, we do not endorse the demonstrator's general suggestion to refuse the breath test): Darryl Genis Demonstrates 7410 Vulnerability.


Any result portrayed was dependent on the facts of that case, and the results will differ if based on different facts.

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Dave Jake Schwartz is an Honors Graduate from UC Hastings Law School, and UC Davis, former Federal Judicial Clerk, and Nationally Qualified Sobriety Tests Practitioner. Member of the California Bar for 30 years, Wine Country resident for over 20 years, handles only DUI cases, including thousands of North Bay DUIs and DMV hearings: first/multiple offenders, minors, seniors, tourists, undocumented immigrants, veterans, probation violations, suspended license, public intoxication, open container, minor in possession, child endangerment, collisions, hit and run, evading, resisting arrest.



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