Forensic Toxicology

March 5, 2025

Expert Testimony: Daubert Standard and Rule 702 in North Carolina DWI Cases

Expert testimony can play a pivotal role in DUI charges in North Carolina. In part, that’s because allegations of impaired driving often involve complicated scientific, forensic evidence and technical procedures—such as chemical breath tests, blood alcohol analyses, and field sobriety testing—that lay jurors or even judges may not fully understand. An expert witness, properly qualified and admitted, can provide insight into such complex matters both for the prosecution and the defense.

This article examines the legal framework governing expert testimony in North Carolina DWI cases, the standards for admissibility, procedural requirements, and practical considerations for using expert witnesses. The discussion is intended for attorneys, legal professionals, and anyone seeking an in-depth understanding of how expert evidence is handled in DWI trials relative to the Daubert Standard and Rule 702.

DMV hearings for willful refusal revocations can feel like a costly, uphill battle—and truth be told, they often are.

February 8, 2025

Breath Alcohol Content Screening: BAC in North Carolina

by Carolina Attorneys

North Carolina regulates alcohol screening under a set of rules involving technical standards, operational procedures, and legal provisions that govern how breath tests are administered and how results may be used in criminal proceedings. Officers rely on portable breath alcohol content screening devices (sometimes referred to as a “PBT” or “breathalyzer”) in the field to detect whether a driver has consumed alcohol. Breath testing devices involve following standards set by the Department of Health and Human Services (DHHS) and must be approved by the Forensic Tests for Alcohol Branch.

This post serves as a primer for some of the important aspects of the North Carolina administrative and statutory framework for alcohol screening devices. It explains the significance of regulations like 10A NCAC 41B .0503 and 10A NCAC 41B .0502, along with the NC DWI laws, to show how our state manages breath sampling and the related BAC results. If you have questions about the specifics of your unique legal matter, or if you want to discuss the role of screening devices in your case, give us a ring or text the Powers Law Firm at 704-342-4357. You may also email Bill Powers directly at Bill@CarolinaAttorneys.com.

Below is a synopsis of the topics covered in this article. Each entry links to a section that describes how North Carolina’s framework addresses the approval and calibration of the PBT and provides a big-picture perspective behind the use of approved alcohol screening devices.

February 5, 2025

Hemolysis, BAC Testing, and Criminal Charges in North Carolina

by Carolina Attorneys

Hemolysis involves the rupture of red blood cells in a blood sample. In the context of criminal charges, this can affect how accurately labs measure blood alcohol concentration (BAC). Mechanical factors like needle gauge selection, centrifugation practices, storage conditions, or simple delays can lead to hemolysis. The result may be an inflated or deflated BAC reading. For someone facing DUI charges or other criminal matters where BAC plays a role, understanding hemolysis, BAC testing, and its implications can help in reviewing the evidence.

If you have questions about the specifics of your legal matter, the legal team at Powers Law Firm is available for consultation. You may call or text 704-342-4357. You may also email Bill Powers at Bill@CarolinaAttorneys.com.

Below is a brief syllabus of the main topics covered in this document. Each entry links to a corresponding section that explains how hemolysis occurs, how labs test for BAC, and why these details may shape legal strategies.

February 2, 2025

Understanding Postmortem BAC – Blood Alcohol Concentration in North Carolina Criminal Defense

by Carolina Attorneys

This article discusses how alcohol normally travels through your body when you’re alive, how that changes once life ends, and why postmortem shifts can influence criminal defense in North Carolina. We will also explore the potential legal implications of an inaccurate or misleading BAC when the decedent—who, in criminal cases, may be considered a victim—had alcohol in their system.

By clarifying the complexities of forensic toxicology, our goal is to explain why thorough investigation and analysis by forensic toxicologists may be an essential aspect of building a defense strategy.

It is tempting to assume that the number on a lab report reflects an exact level of intoxication at the time of death, but the science behind postmortem BAC is often far more nuanced and complicated. Factors such as redistribution, laboratory processing, and even microbial activity can alter the reading—sometimes making it appear higher or lower than it actually was when the person was alive.