I am Joel Brand, a California DUI defense attorney, and in this post I want to address a situation that confuses many people who have just been arrested: you were taken to the police station, or to a hospital, and no one ever handed you a breathalyzer. Instead, officers either drew your blood right away or gave you only the choice of blood. If that happened to you, this post explains why it happened, what California law actually requires, and how that procedural choice can affect your defense.
California Law Gives You a Choice, but Only of the Evidentiary Tests
Under California's implied consent law, once you are lawfully arrested for DUI, you must submit to one chemical test to measure your blood alcohol level. The law requires that officers offer you the choice between a breath test and a blood test. That choice belongs to you, not the officer. When you were never offered breath at the station, the first question I ask is whether officers properly honored that right, or whether they made the choice for you. A violation of the implied consent advisement process does not automatically win your case, but it is a thread worth pulling. You can read more about how implied consent works at our page on refusal to submit to a chemical test.
Why Officers Sometimes Go Straight to Blood
There are several legitimate reasons a breath test may not be offered at the station. The arresting agency may not have a functioning Evidential Breath Testing device available at that location. Officers may suspect drug involvement alongside alcohol, and a blood draw can detect both. In some counties, policy or equipment shortages have shifted agencies toward blood as the default. If you were unconscious, combative, or taken directly to a hospital, blood is often the only practical option. Understanding which of these situations applies to your arrest matters, because some carry procedural protections and some do not.
The Difference Between a Roadside PAS and the Station Evidentiary Test
Many people confuse the small handheld device the officer used at the roadside with the evidentiary breath test. Those are two different things. The preliminary alcohol screening device, sometimes called a PAS test, is an investigative tool. Its result is generally not the number the prosecution uses to prove your BAC. The evidentiary test, whether breath or blood, is the one that carries legal weight and the one you have a right to choose. If you blew into a roadside device and were then taken directly for a blood draw without being offered a station breath test, that sequence may be worth examining. Our library article on post-arrest blood or breath test refusal covers related procedural rules in detail.
What Happens When Officers Do Not Follow the Choice Requirement
If the record shows that officers simply chose blood for you without giving you the option of breath, your attorney may be able to argue that the implied consent advisement was defective. In some circumstances that argument supports a motion to suppress the blood result. Even when suppression is not granted, a procedural irregularity can affect plea negotiations and how the prosecution presents its case. Our overview of motions to suppress evidence in a DUI trial explains how that process works.
Blood Results Take Time, and That Gap Is Not Neutral
One practical consequence of a blood draw instead of a breath test is that you may not know your official BAC number for weeks. The sample goes to a laboratory, and results are returned on the lab's schedule. During that waiting period, the defense has time to gather its own evidence, document your condition that night, and begin building context. Our post on the rising BAC defense is relevant here, because the time between your last drink and the blood draw can affect what the number actually means.
Chain of Custody and Blood Sample Integrity
When your case rests entirely on a blood result, the integrity of that sample becomes critical. California has strict rules about how blood must be drawn, stored, refrigerated, and transported. If any step in that chain was mishandled, the result may be challengeable. I look at the blood draw kit's expiration date, the anticoagulant and preservative levels in the vial, the credentials of the person who drew the blood, and the lab's own quality-control records. Problems in the chain of custody do not always throw out the result, but they can create reasonable doubt. Our article on instrument calibration and testing defenses touches on the broader concept of challenging the reliability of chemical evidence.
Hospital Blood Draws Raise Additional Issues
If you were taken to a hospital and blood was drawn there, the situation is more complicated. Hospital staff draw blood for medical purposes, and police sometimes seek that sample under a warrant or by requesting it from staff directly. Medical draws often use different preservatives than forensic draws, which can affect fermentation of the sample and inflate the BAC reading. Our dedicated post on hospital blood draws and the HAM program covers this in depth.
The DMV Case and Your Blood Result
Remember that your arrest created two separate proceedings. The DMV administrative hearing and the criminal court case each use the blood result, but in different ways and under different standards. The DMV is primarily concerned with whether your BAC was 0.08 or above at the time of driving. Procedural defects in how the blood was obtained may be argued at the DMV hearing as well as in court. You can learn more about the administrative side at our page on understanding the DMV hearing and how to prepare.
What You Should Be Documenting Right Now
While your memory is fresh, write down everything you remember about the moment officers discussed the chemical test with you. Did anyone explain that you had a choice? Did they say breath was unavailable? Did they mention drugs as the reason for going to blood? What exactly did they say before the needle went in? These details can be compared against the arrest report, the officer's body camera footage, and the booking logs. Inconsistencies matter. Our post on common police mistakes during a DUI stop gives you a framework for recognizing where errors are most likely to appear in the record.
How an Attorney Investigates the Testing Process
When I take a case where breath was never offered, I immediately request the agency's internal policy on chemical testing, the maintenance and availability logs for their evidentiary breath device, the training records of the officer who made the testing decision, and the lab's accreditation documents. That discovery process is the same one described in our article on the DMV discovery packet. Evidence in those records sometimes reveals that the agency's own procedures were not followed, which becomes a foundation for your defense.
This Is General Information, Not a Guarantee
Every arrest is different. The facts of your case, the agency involved, the county, and the specific officers on duty all shape what arguments are available to you. Nothing in this post is a promise of any particular outcome. What I can tell you is that a case built entirely on a blood result, especially one where breath was never offered, deserves careful scrutiny. The procedural steps that led to that blood vial are just as important as the number inside it. Our general guide at California DUI defenses is a good next read if you want a broader picture of what defense strategies exist.
If you were never offered a breath test at the station and you want to understand what that means for your specific arrest, you can get a free written case analysis right here on this page. Call me directly at (888) 271-6644. I answer my own phone, 24/7. You can also read more from the DUI blog while you are here.