Chain of Custody in Georgia DUI Blood-Test Cases
Answer:
Blood evidence is the strongest tool the government has to charge and potentially convict someone of DUI, since the law defines the offense in terms of blood alcohol content above .08 — breath tests, by comparison, rely on a mathematical formula to estimate that number. The chain of custody for a blood sample typically runs from the nurse who draws it, into a vial, shipped via FedEx to the GBI, where it’s stored and eventually tested months later. The government must prove the sample was truly yours, properly taken, and that each person who handled, packaged, opened, and tested it can be accounted for.
What “Chain of Custody” Actually Means
Chain of custody is the documented, unbroken record of everyone who collected, handled, transported, stored, and tested a piece of evidence. For a blood sample, that record starts the moment the vial is filled and has to account for every hand it passes through after that — the person who drew it, however it was packaged and shipped, who received it at the lab, how it was stored while awaiting testing, and who ultimately opened and analyzed it. The purpose is to give the court confidence that the sample tested is the same sample taken from you, untampered with and unaltered, from collection all the way to the result.
Why Blood Evidence Carries So Much Weight
Georgia is a per se DUI state, meaning a blood alcohol concentration of .08 or higher is legally sufficient for a DUI conviction on its own, regardless of how a driver appeared or performed on field sobriety tests. Because a blood number can carry that much weight by itself, it’s also the piece of evidence prosecutors lean on hardest — which makes any weakness in how that sample was handled correspondingly important to the defense.
Where the Chain Commonly Breaks
A break anywhere along this chain — at collection, during transport, in storage, or at the lab — gives the defense a concrete basis to challenge the reliability of the result. Common issues include:
- Improper collection procedure or an unqualified person drawing the blood
- Missing, incomplete, or inconsistent paperwork documenting who handled the sample and when
- Gaps in how the sample was stored or transported, including temperature control
- Delays or irregularities once the sample reached the lab for testing
What This Means for Your Case
Because the government has to be able to account for the sample at every step, any gap in that documentation is something a defense attorney can raise to challenge whether the result should be trusted at all. If you have questions about chain of custody in your case and you’re in the North Georgia area, give us a call.
