Blood tests are used in some Florida DUI cases, such as when a breath test is not possible or drugs are suspected. A blood test defense looks at how the sample was collected, handled and analyzed, because each of those steps can be reviewed.
Why blood instead of breath?
Most Florida DUI arrests involve breath testing on the Intoxilyzer 8000. Blood comes into the picture in narrower situations: when a breath test is not possible, for example after an injury, or when drugs are suspected and a breath instrument, which measures alcohol, would not answer the question.
A blood result can be offered to show an alcohol level of 0.08 or higher, or to show that a drug was present. Each kind of result raises its own questions, and each is reviewed differently.
The draw: who collected the sample, and when
The first area of review is the collection itself. The defense looks at who drew the blood, when and where it was drawn, and what materials were used. Each of those details should be traceable in the records produced through discovery.
Timing deserves particular attention. A sample reflects the person's blood at the moment it was drawn, not necessarily at the moment of driving. The gap between the two, and what happened during it, is part of the analysis.
Handling and storage between the draw and the lab
After collection, a sample has to be labeled, sealed, stored and transported, and each transfer is supposed to be documented. That documented path is often called the chain of custody.
Gaps in that record, unclear labels or storage problems can raise questions about whether the tested sample is the one that was drawn and whether it changed along the way. These questions can be explored through the records and through depositions, which Florida allows in criminal cases. Those depositions are narrower in misdemeanor cases, including most DUIs, where the defense generally has to show good cause first.
Lab procedures and what a result actually shows
The analysis is the third area of review. Lab records can show the method used, any quality control records kept with the run, and who performed the work. The people involved in the testing can be questioned in a deposition.
In drug cases there is an added question: what does the result really show? Finding a substance in blood is not the same as showing that the driver's normal faculties were impaired at the time of driving. A valid prescription is not a defense if the driver was impaired, but the state still has to connect the substance to impairment.
How blood evidence fits into the rest of the case
Blood evidence rarely stands alone. It is weighed together with the reason for the stop, any roadside exercises, video and the officer's observations. A motion to suppress may address whether evidence, including a blood sample, was obtained lawfully, and other issues may be raised by different motions or at trial.
A meaningful review needs the full lab file, which arrives through discovery. DUI Lawyers Shield Firm can explain during a free case review which records usually exist in a blood case and how they are requested.
Keep reading
- High BAC DUI in Florida: When .15 Changes the Case
- When Florida Uses a Urine Test in a DUI Case
- House Arrest and Community Control in Florida DUI Sentences
General information only, not legal advice. Every case depends on its own facts, and prior results do not guarantee a similar outcome.
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