I am Joel Brand, and I defend DUI cases across California. If you were arrested for DUI and police took your blood at a station, jail, hospital, or mobile draw location, this post explains why the person who drew it, the paperwork, and the handling of the sample can matter.
Was the person who drew my blood allowed to do it?
In a California DUI case, the blood draw is not just a medical event. It is evidence. That means the prosecution may need to show that the draw was done by an authorized person, in a reasonable way, using procedures that support a reliable result. The officer is usually not the person who draws the blood. It may be a nurse, phlebotomist, medical technician, paramedic, or other trained person depending on the location and agency practice.
The question is not simply whether someone was wearing scrubs or working in a jail. I want to know the person's name, job title, employer, certification or training, where the draw happened, what kit was used, and whether the paperwork lines up with the officer's report. California chemical testing rules can be technical, and I often start with the basics in Title 17 chemical testing rules and the documents connected to the blood kit.
Why the blood draw details matter
A blood test can look more scientific than a breath test, but it is still created by people following procedures. People can make mistakes. A tube can be mislabeled. A form can be incomplete. A sample can sit too long before refrigeration. A blood kit can be expired or missing required components. None of those facts automatically wins a case, but each can become important when the government is relying heavily on the number.
Many clients tell me, "I do not remember anything unusual about the blood draw." That is common. You may have been tired, stressed, handcuffed, or sitting in a holding area. You may not know whether the person used a nonalcoholic swab, inverted the tube, sealed the kit correctly, or documented the time accurately. That is why I do not rely only on memory. I look for records.
Can a bad blood draw help my DUI case?
It can, depending on the facts. A problem with the blood draw may support a challenge to the reliability of the BAC result, the admissibility of evidence, or the weight the prosecutor and judge should give that number. This is general information, not a guarantee of any outcome. The same mistake can matter a lot in one case and very little in another.
For example, if the blood result is close to the legal limit, a timing issue or handling issue may matter more. If the police stopped you long before the blood was drawn, the timeline may connect to a rising BAC defense or the three hour presumption. If the result is high, the defense may focus more on whether the draw, storage, lab testing, or reporting can be trusted. The point is to identify the weak links, not to assume that a lab number ends the case.
Chain of custody after the tube leaves your arm
After blood is drawn, it must travel through several hands. The draw person may label and seal the tubes. An officer may take custody of the kit. The kit may be stored at a station, transported to a lab, logged into evidence, refrigerated, tested, and later retained for possible retesting. Each transfer should be documented.
Chain of custody is the paper trail showing where the sample went and who handled it. A gap does not always make the blood result disappear, but it can raise fair questions. Was the sample connected to you? Was it stored properly? Was it tested by the lab that the report identifies? Were the tubes intact when received? Were there multiple people arrested that night whose samples were handled together? These are practical questions, not technical games.
When I review a case, I compare the police report, blood draw form, property log, lab accession record, analyst notes, and final toxicology report. I also consider whether a motion or evidentiary challenge makes sense under the broader California DUI defenses guide.
What if I do not have my BAC result yet?
That is normal in many blood cases. Breath results are often available immediately. Blood results may take days, weeks, or longer depending on the county, lab backlog, and whether the sample is being tested for alcohol, drugs, or both. The prosecutor may not have the final report before your first court date.
Do not assume no news means good news or bad news. It may only mean the lab has not finished. In the meantime, the DMV process can still move quickly. If you received a pink temporary license or a DMV notice, the deadline to request a hearing may matter even before the blood result arrives. I often look at the DMV discovery packet and the rules for a DMV administrative hearing while the criminal case is still developing.
The citation may list Vehicle Code 23152(a), 23152(b), or both. A blood result can be especially important to a charge under Vehicle Code 23152(b), but the prosecutor may also pursue an impairment theory even when the number is delayed or disputed.
What I look for in the records
I look for consistency first. Does the officer's time of stop match the arrest time, draw time, and booking time? Does the blood draw form identify the same person, same date, and same agency case number? Does the lab report list the correct collection time? Does the property evidence log show the sample was booked promptly?
I also look at the blood kit itself. Was there a preservative and anticoagulant? Was the kit expired? Was a nonalcoholic cleaning solution used? Were the tubes filled and mixed according to the instructions? Was the sample refrigerated? Were there duplicate tubes, and are they still available? These details connect directly to blood testing rules and your right to a retest.
Then I look at the lab work. I want to know the testing method, the analyst, the calibration and quality control records, whether the lab ran duplicates, and whether the reported number is supported by the underlying data. A final one page report is rarely the whole story.
Should I get an independent retest?
Sometimes, yes. A retest can be useful when the original blood result is close to an important threshold, when drug testing is involved, when the lab result does not match the facts, or when there are concerns about storage and preservation. A retest is not automatic, and it is not always the right strategic move. It depends on what is left of the sample, what the first report says, and what the defense is trying to prove.
The timing matters. Blood samples are not kept forever, and different agencies have different retention practices. If you wait too long, the sample may be destroyed according to policy. That is one reason I prefer to request discovery early, preserve evidence, and decide whether a retest makes sense before the case drifts forward.
Practical steps after a police station or jail blood draw
Write down what you remember while it is fresh. Where were you when the blood was drawn? Was it at a hospital, jail, CHP office, sheriff station, or local police department? Did the person identify themselves? Did you see one tube or two? Did the officer read anything to you about breath or blood? Did anyone mention refusal? If there was an issue with consent or refusal, that may connect to separate rules about a post arrest chemical test refusal.
Keep your citation, pink DMV paper, release paperwork, hospital paperwork, and any property receipt. Do not call the lab yourself and try to argue about the result. Do not post about the arrest online. Do not assume the case is hopeless because there was a blood test. A careful review can show whether the government has a clean, reliable number or whether there are issues worth pressing.
You can get a free written case analysis on this page, or call me at (888) 271-6644. I answer my own phone, 24/7, and you can also read more from the DUI blog.
Primary sources
California statutes cited in this article, linked to the official text published by the California Legislature.