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"Infrared Spectroscopy" as a DUI Defense

Alcohol breath test machines have the ability to land people in jail... but they often use technology that can produce a warped result.

The electronic circuitry of breath test devices can get "jammed," leading to false readings

The majority of California DUI arrests and prosecutions depend on evidence of a person's blood alcohol content (BAC).  To produce this evidence, law enforcement agencies almost always use breath testing machines that convert breath alcohol measurement into BAC.

The most common California DUI breath-testing technology is infrared spectroscopy. In its simplest terms, this process reads ultra-fine energy wavelengths that can reveal the alcohol content in a person's breath sample.

Scientists continue to identify inherent problems with this process. These include:

  • "radio frequency interference" (RFI), and
  • conversion errors.

1. "Radio Frequency Interference" (RFI)

Infrared spectroscopy has a proven tendency to pick up "radio frequency interference" (RFI) from surrounding electronic devices such as:

  • patrol car radios,
  • crime lab automatic door locks,
  • cell phones,
  • microwaves, and
  • fluorescent lights.

RFI can affect the electronic circuitry of breathalyzers -- and thereby cause falsely high BAC readings.

2. Conversion Errors

Unlike California DUI blood testing, DUI breath tests do not measure blood alcohol directly. Breath testing devices have to mathematically convert the amount of alcohol present in breath into the amount of alcohol present in blood.

The method used to convert infrared spectroscopy measurements to BAC is based on multiple assumptions that do not always apply. In certain cases, infrared spectroscopy may:

  • show that alcohol is present in a DUI suspect's system when it's really not, or
  • produce a reading that is falsely high.

Our Los Angeles DUI lawyers have seen these errors from infrared spectroscopy lead to wrongful DUI arrests and charges.  Discovering them can "torpedo" the prosecution's most important evidence.That's why we analyze every case we take on in order to discover anything that may benefit the California DUI defense we're building on a client's behalf.

We represent clients throughout Los Angeles, San Bernardino, Orange, Ventura and Riverside counties. Contact us for a free consultation to find out how we can help you.

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The police arrested you for DUI. You gave a blood or a breath sample. The DUI officer confiscated you drivers license. The police released you with a notice to appear in court in a few weeks. Where do you go from here? Our lawyers are here to guide you step by step.