Legal Implications of Blood Alcohol Concentration Testing in DWI Charges: Two Methods of Evidence Presentation

Legal Implications of Blood Alcohol Concentration Testing in DWI Charges: Two Methods of Evidence Presentation

Legal Implications of Blood Alcohol Concentration Testing in DWI Charges

The Two Methods of Offering Evidence of BAC in DWI Cases

When you are charged with driving while impaired (DWI), the State (i.e., prosecution) will try to offer evidence of your blood alcohol concentration (BAC) in two ways. The first is by submitting the results of a breath test, which a certified analyst, often the arresting officer, administers. In most cases, this is done on an approved, calibrated machine located at a police station or a local jail. The second method is by a blood test, which is typically heavily litigated due to various reasons.

Breath Test Results for Admissibility

When law enforcement officers adhere to the North Carolina General Statutes while administering the breath test, the results of the test are admissible at trial. However, any obvious violations of the statutory procedure can make the results inadmissible. In comparison, the admissibility of blood test results is often significantly more contested.

Challenges of BAC Determination Through Blood Testing

Generally, blood testing is conducted when you refuse to take the breath test, or when you have an accident and are transported to the hospital. In such cases, the law enforcement officer must comply with specific statutory requirements to make the blood draw admissible. Once the test is completed, two entities could process the blood draw—the actual hospital where the blood was drawn or the State Bureau of Investigation (SBI) Crime Lab. If the blood draw goes to the SBI Crime Lab, the results take over a year and following compliance with all statutory requirements, they are admissible at trial.

Processing the Blood Draw

When the blood is drawn from the driver, it is transferred to the hospital lab for testing to determine the BAC. However, the procedures and results of the testing are typically only documented in the driver's hospital records. Devoid of a large amount of information, some of which could be used to prove innocence, the results and records can pose issues. For instance, the BAC results are often expressed in increments that are incompatible with North Carolina's statutory definition of impaired driving. Therefore, the State must introduce a professional who can convert the hospital results into the appropriate units that the judge or jury can apply to the statutory definition of drink driving determined by the state legislature.

Admitting Hospital Records into Evidence

Before the results can be presented to the judge or jury, the actual hospital records must be introduced into evidence by the state. There are several ways to admit hospital records classified as business records under the North Carolina Rules of Evidence, with the most often used being subpoenaing of the records from the hospital and requiring the hospital administrator to include an affidavit indicating the things they would testify to at trial regarding storage of the records. Alternatively, someone from the hospital can bring the records, testify to the way the records were stored, testify that they are the custodian of the records, and tender the records into evidence. However, whether through a subpoena or testimony, the state must follow through with the appropriate statutory requirements to admit hospital records into evidence.

Limitations of Medical Records as Evidence

Unlike with the SBI Crime Lab, medical records do not offer sufficient detail to answer many testing reliability and accuracy questions. Therefore, criminal defense lawyers utilize various strategies, including challenging the machine calibration, testing procedure, blood test operator, and accuracy, to advocate effectively for the client and build a robust defense.

Defending Against DWI Charges

There are multiple ways the State can prove BAC, but there are also multiple ways that your case can be appropriately defended under similar circumstances. Effective defense strategies, such as challenging the admissibility of the medical records or introducing procedural errors, can help in advocating for the client and building a stronger defense. In Johnston County, we have seen instances where the court refused to admit medical records as evidence for lack of proper foundation, much to the benefit of the defendant. At Mast Law Firm, our experienced attorneys can handle all traffic court cases and DWI charges. Contact us today to learn more about our legal services.

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Legal Implications of Blood Alcohol Concentration Testing in DWI Charges: Two Methods of Evidence Presentation