Blood alcohol tests often play a critical role in DUI cases, but they’re not infallible. While these tests are considered reliable, several factors can lead to inaccuracies or inconsistencies. That’s why it’s essential to turn to the help of a DUI defense attorney.
As a defendant, understanding what might challenge the results of a blood alcohol test can make a significant difference in your case. That’s why you should rely on the guidance of the Leier Law Office, LLC in Fort Collins, Colorado. We’ll help you explore the forms of evidence that could cast doubt on blood alcohol test results and how they might impact your defense.
Understanding Blood Alcohol Tests
These tests measure the concentration of alcohol in your bloodstream, often expressed as blood alcohol content (BAC). The legal BAC limit for a DUI in Colorado is 0.08, the legal presumption for a DWAI in Colorado is .05, and the legal limit for minors is .02. When your BAC is at or above these levels, it can serve as evidence of impairment.
The process of administering, analyzing, and interpreting blood alcohol tests is far from straightforward. Errors during any stage could affect the results — and the strategy of your DUI defense attorney. The fact that so many variables can influence a test result highlights why such evidence shouldn’t be accepted at face value without scrutiny.
Problems With Sample Collection
One of the first areas to examine is the collection of blood samples. Mistakes during this step can lead to inaccurate readings. Some common issues include:
Improper use of antiseptics: If alcohol-based antiseptics are used to clean the site of the blood draw, they can contaminate the sample and artificially raise BAC levels.
Failure to follow proper procedures: Medical personnel must follow strict protocols when collecting blood samples. Deviations from these protocols can compromise the sample’s integrity.
Unqualified personnel: Blood draws should be conducted by trained professionals. If the person performing the draw lacks proper credentials, it might invalidate the test.
Use of expired or contaminated equipment: Using expired collection tubes or contaminated needles can affect the reliability of the sample.
In some cases, these errors might be obvious, such as visible contamination or improperly labeled tubes. Other times, uncovering these issues may require a detailed review of the collection process and associated records. While collection issues are a significant concern, the testing process itself also presents opportunities for error.
Issues With Laboratory Testing
After the blood sample is collected, it must be analyzed in a laboratory. Errors in this phase can lead to inaccurate BAC results. A DUI defense attorney should consider these potential problems:
Mishandling or mislabeling of samples: If samples are mislabeled or mishandled, it could result in mix-ups or contamination.
Failure to maintain proper storage conditions: Blood samples must be stored at specific temperatures. Improper storage can cause fermentation, which might increase the alcohol concentration.
Inadequate equipment calibration: Laboratory equipment must be calibrated regularly to provide accurate results. Failure to do so can lead to false readings.
Human error in analysis: Lab technicians are human, and mistakes such as misreading data or improper operation of machinery can occur.
Lack of independent review: Some laboratories fail to implement secondary reviews of test results, which could catch errors before the results are finalized.
To challenge these issues, your DUI defense attorney might review maintenance logs, technician training records, and laboratory certifications. Identifying discrepancies in these areas can weaken the reliability of the test results.
Laboratory errors aren’t the only issues that can challenge blood alcohol test results. Legal and procedural missteps can also weaken the prosecution’s case.
Violations of Legal Procedures
Law enforcement and legal procedures surrounding blood alcohol tests must comply with strict rules. Any deviation from these requirements could be grounds to challenge the test results. Key issues include:
Failure to obtain proper consent: In Colorado, express consent laws require drivers to submit to chemical testing, but law enforcement must still follow protocols for obtaining consent. If consent wasn’t properly obtained, the results might be inadmissible.
Lack of a valid search warrant: If officers fail to secure a search warrant when required, it could render the test results invalid.
Chain of custody issues: The prosecution must demonstrate that the sample’s chain of custody was unbroken. Missing documentation or unclear handoffs could cast doubt on the sample’s integrity.
Improper timing of the test: Delays between the alleged offense and the administration of the blood test can raise questions about the accuracy of the results.
In some instances, procedural violations may even result in the dismissal of charges. Highlighting these errors can be a powerful strategy for your DUI defense attorney. In addition to procedural concerns, medical and physiological factors can also impact blood alcohol test results.
Medical And Physiological Factors
Your unique medical and physiological characteristics might explain discrepancies in blood alcohol test results. Consider the following factors:
Rising blood alcohol levels: Alcohol takes time to absorb into the bloodstream. If your BAC was rising at the time of the test, it might not reflect your BAC while driving.
Medical conditions: Conditions such as diabetes or GERD (gastroesophageal reflux disease) can produce substances in the body that mimic alcohol, leading to false positives.
Medications: Certain medications can interact with alcohol in ways that alter BAC results or create inaccuracies.
Individual metabolic rates: Everyone processes alcohol differently. A slower or faster metabolism could result in a BAC that doesn’t align with actual impairment.
Dehydration or fasting: These conditions can sometimes cause exaggerated BAC results due to changes in how alcohol is distributed in the body.
Exploring these factors often requires input from medical experts. Their testimony can shed light on how such issues may have influenced your test results. Beyond medical issues, other pieces of evidence presented by your DUI defense attorney could challenge the validity of blood alcohol test results.
Other Evidence That Can Challenge BAC Results
In some cases, additional evidence might call the blood alcohol test into question. Examples include:
Witness testimony: Witnesses who can attest to your sobriety before driving might weaken the argument that you were impaired.
Video evidence: Dashcam or surveillance footage showing you performing tasks that require coordination could counter the results of a blood alcohol test.
Field sobriety test performance: If you performed well on field sobriety tests, it might suggest that the BAC results don’t accurately reflect impairment.
Expert testimony: A forensic toxicologist or medical expert can review the blood alcohol test and provide insight into potential inaccuracies.
Driving behavior: Evidence showing that you were driving safely and within the law can be a powerful counter to claims of impairment.
Moreover, a DUI defense attorney may ask for your own account of the events leading up to the test can provide context. For instance, if you had a small amount of alcohol shortly before being pulled over, it might explain why your BAC was rising. Additionally, documenting any external factors — such as environmental conditions or fatigue — can add context to your case.
Reach Out to Us Today
Blood alcohol tests might seem like definitive evidence in DUI cases, but they’re not without flaws. Issues with sample collection, laboratory testing, legal procedures, and medical factors can be challenged by a reliable DUI defense attorney. Reach out to us at The Leier Law Office today for help with DUI charges in Loveland, Greeley, Windsor, Evans, and Fort Collins, Colorado.
