Successfully Handling DUI Cases in Los Angeles for 19 Years . Call Us Now at 213-479-5322

Blog Archive

Gas Chromatogram

Here’s what the graph from a Gas Chromatogram looks like


“What is a gas chromatogram?”

Seems like a simple question, but it gets to the heart of who’s out there purporting to be a DUI Defense Attorney. Whether the person knows the answer shows whether DUI defense is what they do – or just another in a long list of things they advertise for.

The answer is:

A chromatogram is a graphic representation of the test that’s done by the cops to determine the accused’s blood alcohol content at the time of the test.

If the person who wants to be your DUI Defense Lawyer can’t answer the question, or says it doesn’t matter, you need to thank that person for their time and leave.

I was recently in Court fighting to get the Chromatograms for my client and I was the only one in the room who knew what a Chromatogram was. I had to explain what Chromatograms are to the Judge AND the Prosecutor. Other Lawyers were taking notes about chromatograms – because they didn’t know.

Judges and Prosecutors ask all the time: “Why do you need to see that?” because most other lawyers aren’t asking to see these essential test results.

Blood tests can be fought – ALL DUIs can be fought – and knowing whatc hromatography machines are and exactly how they work is essential to that fight. Gas chromatography machines are NOT infallible. If you know where to look, you can find that the machine or the blood sample are probably contaminated.

Even if your DUI doesn’t involve a blood test, if it’s a refusal or a breath test, not knowing the answer to this question discloses that the person you asked doesn’t really know what he or she is doing. Chances are they’re just saying what you want to hear in order to get hired and they will just be going through the motions during your case. Chances are no matter how great what they say sounds,when they’re trying to get hired, you will end up pleading guilty to a DUI.

If your case does involve blood testing, the Lawyer who can’t answer your question will probably end up telling you, “It’s a blood test, there’s no way to fight that.” Without even looking at the chromatograms!

You’re going to end up spending thousands of dollars, even if you hire a cheap “Do Nothing” Attorney. It’s important to your future; you should know what to ask and know what you’re getting. Even if you settle for the guy who doesn’t know what a chromatogram is, you should know your Lawyer’s limitations.

Blood Test or Breathalyzer: Which Test Makes It Easier To Fight Your DUI?

I used to say that it didn’t matter which test you took, blood or breath, because both of the tests were subject to attacks based on scientific problems with the tests themselves.  As a result of the recent decision of the California Supreme Court in People v. Vangelder, I have changed my recommendation.  I now recommend that people who have been arrested for DUI choose a blood test as their implied consent test.

The reason is that a lot of the problem with breath testing is that it doesn’t directly measure the amount of alcohol in your blood. Alcohol in your breath does not affect your ability to drive, either physically or mentally. Only alcohol in your blood does. If you are absorbing (which can happen for up to 6 hours after drinking) the amount of alcohol in your breath is much higher than the amount of alcohol in your blood.

The Vangelder decision has done away with most attacks on breath.

The California Supreme Court, in a decision that flies in the face of science and due process, has said that when the legislature wrote the DUI law all of the problems with breath testing were known and the Court must assume the legislature knew about the problems when they wrote the law the way they did. The Court also said since the machines used to test breath in California are on the Federal approved products list, the problems inherent in their design are off-limits for attack. The problem is that there is no requirement that products on the list be scientifically tested.

Still, the Court left open an avenue of attack, but it’s hard to use because you need the right expert to testify.  The Court has said that you can attack the specific machine when it was not used properly.   When dealing with a breath test, a proper defense has to be carefully laid and it is much easier to attack the fermentation that occurs in blood taken by cops.

The method by which blood is collected and measured is discussed in my article How Blood Testing Works.

The fermentation problem is discussed in my article Fermentation: The Big Problem With Blood Tests.

The problem with breath testing is discussed further in my article Breath Test Science in DUIs?

If you have any questions about whether to take a blood or breath test at all,  how to defend against them, which test to take or DUI in general:

Call me at (213) 479-5322.  If you have an opinion, please leave a comment.

Problems With the CA DUI Blood Test: Fermentation and Contamination.

The first problem with blood testing for alcohol is that it’s impossible to tell how much alcohol was present at the time of the blood draw and how much alcohol was created by later fermentation of the sugars in blood by microorganisms. In other words, the microorganisms naturally present in the blood begin to produce alcohol in the sample.

Chemical Model of DUI Blood Test Fermentation

Chemical Model of DUI Blood Test Fermentation

What happens while the blood is stored is that the glucose (sugar) naturally occurring in the blood is converted by microorganisms (Candid Albicans and Saccharomyces Ellipsoideus, among others), through the process of fermentation, to alcohol.  Fermentation is a fancy name for eating.  These microorganisms eat the sugar, remove energy from the sugar and leave carbon dioxide and alcohol as waste products. Studies show that over .20% BAC can be produced in improperly stored samples.

When the blood is drawn, if it is not done by accepted medical practices, the sample can be contaminated.  Simply using a non-alcohol sterilizing agent on the area where the blood is drawn is not enough to prevent contamination.  Improperly sterilizing the area can cause contamination.

Even if the area of the blood draw is properly sterilized, microorganisms present in the blood can cause  fermentation.

A preservative/anti-coagulant is supposedly added to blood drawn by the cops, but no lab in California tests for the presence of preservative/anti-coagulant.  So we never know if it was present in the proper amount or if it was properly distributed in the sample. In fact, breweries add the preservative supposedly used by law enforcement to their beer to ensure that only the right microorganism ferments their beer.

Once collected, the sample is supposed to be stored at or near freezing (32 F) and the test is supposed to be performed with 7 days to minimize fermentation. This is rarely, if ever, done.The sample is usually stored for 4 weeks, unrefrigerated.

Another problem is that the sample can never be proven by the State to contain only alcohol present before the blood was taken from the body.  When the chromatograms of the blood tests are reviewed it is often shown that acetaldehyde is present.  Acetaldehyde is a precursor to alcohol produced in the microorganism fermentation process  after the blood is taken.

In addition to the fermentation that takes place post-draw, there can also be further contamination that can be seen in the peaks in chromatograms.  A proper peak is symmetrical and shows only alcohol.  An improper peak is broad  or has a front or tail that is not symetrical. An improper peak is evidence of contamination in the sample.  It means that there is more than one volatile organic compound  in the tube at the same time and not only alcohol.  So the test reads higher in alcohol than it really is.That means that the State can never prove what the BAC is because the amount that is coming out that is alcohol can never be determined.

Read more about How Blood Testing Works.

Why Blood Testing is now the implied consent test that I recommend is discussed in my article ” Blood Test or Breathalyzer? Which test should I take?”

If you have questions about blood tests, their problems, which test to take or DUI in general:

We’re here to fight for you. Free Consultation. Call me at (213) 479-5322.

If you have an opinion, please leave a comment.



Chemical Model of fermentation in DUI Blood Tests

Chemical Model of Fermentation in a DUI Blood Test

How the CA DUI Blood Test Works.

As part of the California Implied Consent Law, a person arrested for DUI is given the option of taking a breath or a blood test. For reasons I discuss elsewhere, blood testing is now my recommended choice.

Remember: unless you are under 21 or on DUI probation you are free to refuse the handheld Breathalyzer given at the scene of the DUI stop AND I advise that you so refuse.

When you opt to take a dui blood test, the cop takes you to a hospital, or in some cases they take you to a phlebotomist (vampire) that they have on staff at the police station. The blood drawer is supposed to draw the blood by using accepted medical practices.

The cop then takes the blood vial and puts it in an envelope.  He puts the envelope in the unrefrigerated evidence room.  At some point, the blood sample is moved to the crime lab.  The blood is tested at the lab.  It usually takes 3-4 weeks before the lab technician gets around to testing the blood.  This creates a problem in that the blood becomes contaminated and the sample is ruined by fermentation.  I discuss fermentation here: Fermentation: The Big Problem with the DUI Blood Test in CA.

When it is finally time for the actual blood testing, the lab technician takes the vial and uses a syringe to draw off two 1 millimeter samples.  The samples are then put in an oven and heated.  The gas above the blood in these samples is called the headspace.  Once heated, the lab tech takes a syringe and draws off a very small sample of the headspace gas.  This gas is then transferred to the gas chromatagraph.

To this gas a constant amount of Isopropanol is added.  The Isopropanol is used as a baseline reading. A carrier gas, usually hydrogen, is used in the tube.

The science behind blood testing relies on headspace gas chromatography flame ionization detection.  Gas chromatography is a process by which the various volatile organic compounds present in the gas sample are separated and measured. The gas is injected into a tube.  The different volatile organic compounds take different amounts of time to go through the tube.  For instance, in the sample chromatogram linked to below, ethyl alcohol (ETOH) comes through at 0.85 minutes.

Diagram of a Chromatogram Reading (Notice in the diagram linked to there are two peaks to the left of the alcohol peak. These are other volatile organic compounds in the sample that inidicate that (1) this sample is contaminated and (2) the blood has fermented after it was drawn. The peak farther to the left, at about 0.64, is the injection peak which shows when the sample was injected into the tube.)

There are two samples,and in the better method of blood testing, two different tubes are used so that it takes each of the volatile organic compounds a different amount of time to go through each tube (the amount of time it takes to go through the tube is called elution).  When only one tube is used, you can’t tell whether the different volatile organic compounds are interfering with the measurement of alcohol no matter how many times you run the sample through (when two different substances come through the tube in the same time, this is called co-elution).

At the end of the tube, there is a flame.  When the alcohol (ETOH) comes through the tube it is burned off and the increased ionization is measured.  The hydrogen carrier gas has a base ionization rate.  When the various organic compounds come through, the increased ionization is measured.  The measurement creates a spike.  As I discuss elsewhere, a good spike is symmetrical. A bad spike is not symmetrical or has a long foot at one side. The one linked to above has an asymmetrical foot on the right side. The spike doesn’t resolve to the base line until almost 1.0 minute.

The area under the spike is measured using calculus.  The numerical value is the amount of alcohol in the blood which is then translated into grams/210 milliliters. A more sciency explanation can be found here.

This is how blood is tested.  There are big problems with blood testing that you can use to fight your DUI case, which I discuss in my article Fermentation: The Big Problem With Blood Tests.

If you have questions about blood tests, it’s problems, which test to take or DUI in general call me at (213) 479-5322 or fill out the easy form at the right. I’ll be happy to give you a Free Consultation or answer ny questions you have. And if you have an opinion, please leave a comment.

Beers clinkingTelling Cop You Had One Or Two Beers Is Usually the Wrong Answer.

Those pulled over for a traffic stop invariably tell the arresting officer that they had “one or two beers” when asked.  This is a mistake for two reasons.  First, the person pulled over is under no obligation to assist the police officer in building a case against them.*  It is axiomatic that unless you are a lost six year old, the police officer is not there to help you.

Second, if it’s not true that the person had one or two beers, then it will come back to discredit them and will limit their options at the DMV and trial.  If the person blows around .08, then they had approximately 4 drinks. Widmark’s formula** tells us that every drink raises the BAC of the average man by approximately .02.  Thus, a .08 BAC means that the person imbibed 4 drinks.  So when you tell the officer that you only had one or two beers and you blow .08 and later the alcohol tech testifies that you must have had 4 drinks based on Widmark’s formula, your credibility is shot.

Again, I cannot stress enough how important it is NOT to answer the cop’s questions when pulled over for a traffic infraction/DUI investigation.  {I wouldn’t even answer, “Do you know why I pulled you over?”} Contrary to popular belief, your statements to the officer are not made inadmissible because he didn’t read you your Miranda rights.  The US Supreme Court in Berkemer v. McCarty has said that answers to post-stop/pre-arrest questions (the US Supreme Court actually said 1-2 questions; in California the DMV and Courts stretch that to include the 23-30 DUI investigative questions asked by officers) are not constitutionally protected by Miranda. Your statements will be used to contradict any testimony you later give.

The second answer that is almost universally given in one form or another is to the question “When did you start/stop drinking?. The detainee’s instinct is to make the drinking as long as possible from the stop and answers accordingly.  This may impact a defendant’s credibility later, after the way alcohol behaves in the body is explained to him, and it is too late to tell the truth.  In most situations, the closer to the stop the person was driving the better for them.

This is for two reasons: First, breath alcohol in the absorptive phase is higher than actual Blood Alcohol.  So, when given a breathalyzer test in the absorptive phase, what the machine reads will be higher than what is actually in your system. Commonly used breath  testing machinery manuals state that it is improper to use the machine for 120 minutes after the person stops drinking because of this.

Second, because alcohol is absorbed over time and it can take between 50 minutes and 2 hours (or longer after you eat) to fully absorb alcohol, the person’s BAC at the time of driving may be less than .08.  An answer by defendant that pushes the time drinking stopped further back will be used to evidence that the Defendant is in the elimination phase and his BAC was higher at the time of driving. See Graph.

* Again, if you have NOT been drinking, cooperate with the police.  If you have been drinking, even a little bit, it is highly likely that regardless of whether you cooperate you will be going to the station, so why give the police evidence that will later be used against you if you are charged?

** Widmark’s formula was developed in the laboratory under strict controls. It is probably not scientific when discussed by a alcohol tech where the only variable that is objectively added into the formula is BAC at some random point after the stop.  Further, Widmark’s formula requires imputting a constant based on the ‘average man’ or ‘average woman’.  Anyone average out there?

Here’s How the Breath Test Works in Los Angeles County.

In Los Angeles, the CHP and LAPD use the Intoximeter EC/IR machine to breath test those they arrest for DUI. This is the test that you should not refuse (the implied consent test). The one given at the police station.

The EC stands for electrochemical and this is how this machine tests the amount of alcohol in the subject’s breath. There is a small wafer about the size of a quarter in a chamber inside the machine. The wafer is covered in platinum stretched thinly over an acidic electrolyte. A positive electrode is attached to the top of the disk and a negative electrode is attached to the bottom of the disk.

A small (1 milliliter, 0.001 liters, 0.1 cubic centimeters) sample of the subject’s breath is drawn into the chamber containing the platinum disk.* The breath is drawn at the end of a sustained breath to insure that deep lung air is tested. A portion of the 1 ml sample alights on the platinum.

When the alcohol vapor in the breath sample lands on the platinum/electrolyte, the O-H bond of the alcohol (C2H5OH) is oxidized. The positive H ion at the end of the molecule is removed and floats to the bottom of the disk. This creates an abundance of electrons (-) at the top of the disk and an absence of electrons on the bottom because of the migration of the H(+) ions to the bottom. the electrons then move from the positive electrode at the top of the disk to the negative electrode at the bottom of the disk.

This creates a charge in the fuel cell which is led off by the negative electrode and measured. The oxidation process creates a net of two electrons per molecule of alcohol. The greater the amount of alcohol present in the test chamber, the more electrons produced.

The IR in EC/IR stands for infrared. Infrared is used to control for mouth alcohol in the EC machines because the do not do so on their own (traditional machines contain a slope indicator to control for mouth alcohol). Infrared technology shines an infrared beam (across a chamber filled with mouth air). The alcohol in the mouth air absorbs the infrared at 3.45 microns and 9.5 microns.

* An average male adult’s lung volume is 4.8 liters or 4800 milliliters. The sample size is 1/4800 of its representative population. Blood Alcohol is measured statutorily as grams per 210 liters.


If you  have been given a Breath test and registered,  there are ways to fight a DUI conviction.. We know the science aand we will fight for you. Call Edward J. Blum at 213-479-5322 or fill out the easy form at right for your Free Consultation.

What do surprise balance tests performed for the first time at the side of the road have to with sobriety?

Nothing. There are numerous problems with field sobriety testing including, but not limited to, (1) There is no baseline of your ability to do the FSEs when you have zero alcohol in your system. (2) The tests are supposed to be standardized, that is the cops are supposed to do them exactly the same every time. They rarely do the tests according to how NHTSA says they are supposed to be done. (3) The cops are looking for evidence against you. The only thing recorded will be what they think you did wrong. (4) The tests measure balance, but they take away your means of keeping balanced: feet shoulder width apart, looking at the horizon, and keeping your head level for inner ear balance.

The bottom line is: If you are stopped by the cops, and if the cops ask you to perform these exercises, politely decline to do the FSEs UNLESS you have not had anything to drink at all. The results can only hurt you.

A Field Sobriety Test is a very  subjective set of divided attention tests. (For the record, most DUI Defense Lawyers refer to them as exercises, FSEs not tests). The officers will always say they aren’t passing you or failing you, they are ‘looking for CLUES’. And the cops will always say you “exhibited all the clues” of intoxication in their field sobriety testing.

There are two kinds of FSEs: Standard and Non-standard. Standard FSEs are those that have been shown to have some correlation to being under the influence in a NHTSA (National Highway Traffic Safety Administration) non-peer reviewed study.* The Standard FSEs are: the Horizontal Gaze Nystagmus (HGN); the Walk and Turn; and the One Leg Stand.

The Non-Standard tests include; Romberg balance, touching your nose with your finger; touching your thumb with your finger; or, reciting the alphabet (backwards or forwards, start with ‘Q’).

Horizontal gaze nystagmus is the test where the cop holds the pencil or his finger 12-15 inches from your face, level with your eyes and moves the it side to side. The cop will say they are looking for 6 ‘clues’ in this test, 3 in each eye: equal pupil size, lack of smooth pursuit, and nystagmus (jerking) of the eye at the extremes. There are really about 20 things they are looking for, including failing to follow instructions and swaying from side to side.

Exhibiting any ‘clue’ can be used in determining you are under the influence. 50% of the population has nystagmus at the extremes when sober. There are dozens of things other than alcohol that cause nystagmus, including it being late at night. (Hint: most DUI stops are late at night.) This is actually a test properly performed by trained Opthamologists (eye doctors) using sophisticated equipment.

In the Walk and Turn test, you walk 9 steps up, execute a complicated turn and walk nine steps back. Not standing with your left foot in front of right, missing toe with heel (more than 2″), not turning around with small steps, and losing balance are all ‘clues’ that you are under the influence. You are not given the grading criteria during the instruction phase. Most people can’t do this sober. Older people, overweight people or people with balance, leg or foot problems cannot usually do this.

In the One Leg Stand, the cop instructs you to raise your leg and count until he says stop. There are 18 ‘clues’ the officer is looking for. Mostly he is seeing whether you are able to keep your balance past 25 seconds. In this test you are instructed that if you put your foot down, just to pick it up and keep going. One of the ‘clues’ that will be held against you is putting your foot down.

The Non-Standard field sobriety tests are even more absurd.

In the Romberg, the cop instructs you to close your eyes and tilt your head back, count silently in your head and estimate 30 seconds. There are 18 ‘clues’ the cop is looking for here. Mostly they want to see whether your time sense is affected by being under the influence. They will judge you on how close to 30 seconds your estimation is. The instructions say that if you are within 10 seconds +/- you pass.

For more information about the field sobriety tests or to set up a consultation with me to talk about your specific case – Call 213-479-5322 or fill out the easy form at right.

* Marceline Burns, one of the psychologists who developed the battery used in field sobriety testing has said the tests don’t show either a specific blood alcohol concentration or impairment for the purpose of driving.

A good case explaining how to fight an checkpoint arrestMan and CHP at checkpoint Arrest came down recently in the San Francisco Appellate Division entitled People v. Alvaredo.  Alvaredo was stopped at a DUI Checkpoint.  He was arrested for DUI and his Attorney moved to suppress the evidence, including the breath test, because the cops did not follow the procedures established by the California Supreme Court in Ingersoll v. Palmer for DUI checkpoints.  The Trial court denied the Motion to Suppress.  The Court of Appeal reversed the denial of the Motion to Suppress because three important and one not-so-important factors were missing.

The Ingersoll factors are:

(1) Whether the decision to establish the checkpoint, the selection of the site, and the procedures for operation are established by supervisory law enforcement personnel;
(2) Whether motorists are stopped according to a neutral formula;
(3) Whether adequate safety precautions are taken, such as proper lighting, warning signs, and signals, and whether clearly identifiable official vehicles and personnel are used;
(4) Whether the location of the checkpoint was determined by a policymaking official, and was reasonable;
(5) Whether the time the checkpoint was conducted and its duration reflect “good judgment” on the part of law enforcement officials;
(6) Whether the checkpoint exhibits sufficient indicia of its official nature (to reassure motorists of the authorized nature of the stop);
(7) Whether the average length and nature of detention is minimized, and;
(8) Whether the checkpoint is preceded by publicity.

 In Alvarado, the Court found that the San Francisco Police Department had not followed (1), (4), (7) and of lesser import (8)(Banks)*.  Because the Police did not establish the procedures to be used at a command level, did not determine whether the location was beneficial for the purpose of deterrence, did not minimize the length and nature of the detention and failed to publicize the DUI checkpoint in advance, the Court held that the checkpoint was unconstitutional.

The Court admits bewilderment with the prosecution in its holding. Stating that even though the state had access to the same Ingersoll factors, they seemed to put on no evidence to sustain their burden of proof under Wilder.**

Avoid being arrested at a DUI Checkpoint. Because the cops are supposed to give advance notification of where and when a checkpoint will be held, you can avoid checkpoints by checking back here because I post the DUI checkpoints when I learn of them.

Inherent in the checkpoint requirements is also that there must be a release valve where people who do not want to wait in line at the checkpoint can avoid it.  The Supreme Court has held that people seeking to avoid a checkpoint cannot be stopped. However, if you violate the Vehicle Code in avoiding the checkpoint, the police can stop you for the violation. So making a U-Turn in the middle of a block, which is illegal, will bring you to the police’s attention.

See related articles on What To Do At A DUI Checkpoint and Drug Testing at DUI Checkpoints.

The way to fight your arrest at a DUI checkpoint is to know the law and know how to use the law to hold the police accountable for following proper procedure. If you’ve been arrested after being stopped at a DUI Checkpoint contact us at (213) 479-5322 to learn how we can fight and win your case for you.

* The Alvarado court properly points out that Banks does not do away with the necessity for advance publication of the checkpoint, it merely states that lack of advance publicity alone will not invalidate the checkpoint.
** Wilder holds that where there is a warrantless search the state bears the burden of proving the justify the search and seizure.

The DUI Drug Test At DUI Checkpoints in California: Don’t Do it.DUI Drug Test machine on CHP Car

Portable drug tests at DUI Checkpoints are the LAPD’s new way to invade your privacy while you’re a guest at one of their numerous checkpoints (LA and other counties have hundreds of thousands of dollars of checkpoint grant money they need to spend).

The test purports to be able to tell if the subject has amphetamines, marijuana, cocaine benzodiazepine (the active ingredient in prescription drugs like Xanax) and other illegal substances.

Before you swab, remember: the only test you HAVE to take when arrested on suspicion of DUI Drugs is a Blood Test after Arrest. (This is based on the Implied Consent laws, not HAVE to take based on Fourth Amendment grounds.) The swab test when administered at the checkpoint is the equivalent of the PAS handheld breath tester given to those suspected of being impaired by alcohol. Because of that, there should be an admonition stating that you are free to refuse to take the test without consequence. But there isn’t.

There should be an admonition read, because you are free to refuse the test. So refuse to take the test if asked.

Once arrested the Supreme Court has said that taking a sample of your DNA is a constitutionally reasonable seizure. However, the law in California doesn’t provide for the admission of these drug swab tests as evidence in a DUI, like a Blood Test would be admitted. Many foundational issues exist with respect to the admission of a new technique like saliva swabbing for drug detection.

The LA City Attorney has yet to use one of these portable drug test swabs in an actual trial.

Check out additional articles on What to do at a DUI Checkpoint and Case Law for DUI Checkpoint Arrests.

If you are going out this weekend, make sure to check here for the location of DUI Checkpoints. If you have questions about checkpoints, DUIs or DUIs with drugs call me at (213) 479-5322 or visit my website at

How Can We Help You?

Your Name (required)

Your Email (required)

Your Phone Number

Your Message / Case Info / Best Time to Call

Your information is 100% Confidential.
Apex Chat

Copyright 2014 The Law Office of Edward J. Blum