With over twenty-five years of experience in DUI cases, I've witnessed the various tests used to measure blood alcohol content. The tests we commonly encounter are the breath machine and blood tests. While urine tests were once an option, the legislature has now limited the options to blood or breath tests.

However, other available tests relevant to a Vehicle Code 23152a charge include the field sobriety test, which is designed to assess whether someone can safely operate a motor vehicle. As a result, many people are unaware that they don't need to provide a blood alcohol reading by breath, blood, or urine.

Field sobriety tests, which are often subjective, can also be used to determine intoxication. The officer's observation that you smelled of alcohol and appeared intoxicated can be used as evidence for a DUI, even without a .08 BAC reading from a breath or blood test.

If you're charged under VC 23152a, it means you had alcohol in your system and were unable to safely operate a motor vehicle. This section also considers whether your BAC was .08 or higher, which is the legal limit in Los Angeles, California.

In addition to the field sobriety test, they're going to look at the way that you're walking. They're going to look at the way that you're talking. They're going to look at how you were driving when you were either pulled over or some people got into an accident.

If you crash into somebody, there's an argument you can't safely operate a motor vehicle – then the next question is, can they prove that you had alcohol in your system?

There are several ways to do that. Again, suppose you smell like alcohol, and you're acting like an intoxicated person. In that case, the police could undoubtedly put those pieces of evidence in at a potential jury trial and then let the jury decide. Of course, it's best for them if they have some reading.

What Is The Best Way To Measure Blood?

In my opinion, and I think based on science, getting somebody's blood is the most accurate test of the tests that are available to law enforcement and prosecutors who deal with DUI cases in Los Angeles County.

If they can get your blood, then they can get pretty darn close to your blood alcohol level, and it kind of rules out a lot of arguments that you can argue when you take somebody's breath.

Of course, you could still argue that the sample they took was contaminated if you have the evidence available to do that. Depending on when they take the blood, other things could be an argument if they're waiting three to four hours to take somebody's blood; who cares that their blood alcohol level was three to four hours after driving?

Blood Alcohol Level At Time of Driving

For a DUI in LA County, we want to know the blood alcohol level at the time of driving. They're going to have to use an expert to attempt to extrapolate backward from the point when they take the test – either by way of a breath test or a blood test – what was the result then, and now how do you go and say what the outcome was one hour, two hours, three hours later.

The bottom line is that blood is the most accurate. There is some accuracy in that regard, particularly with breath tests, but those tests can be influenced. If the machine used to test the breath is not working correctly, that happens all the time. It needs to be calibrated correctly.

There's an issue with it. It's taken out of service close in time to when your breath was born, then we've got an argument that the machine wasn't working right, and whatever your BAC was is not accurate.

Less Accurate Breath Test

Also, I think it is commonly agreed among experts in the DUI field that the machine used to test your breath at the police stations across LA County has an error rate of .02. So, that means if you blew a .08, you could have been a .08. You could have been a .90.

So, you'll have a different accuracy. Obviously, the closer you are to the legal limit if they're trying to get you for Vehicle Code Section 23152b, the stronger argument you have when looking at everything from a totality of the circumstances that you were not driving under the influence and, therefore, should not be prosecuted.

So, I guess it would be fair to say that the second-best test for a DUI in Los Angeles County is the breath. Now, don't confuse the breath tests at the station with the breath test typically used in the field.

The Preliminary Alcohol Screening (PAS) Device is not as accurate as the blood test or the test administered at the station. They've had all kinds of problems with that PAS Device test, and you didn't even use to be able to say what the reading was on that in court to try to prove that somebody is a DUI.

Now, the courts have given that some more credence. But the bottom line is that the test is not accurate. The defense can always present its expert to attack and make it look unfavorable and unclear.

Depending on how high your blood alcohol level was, how many drinks you had, how you were walking, talking, driving – that's all going to be impacted in any DUI case that you get yourself involved with.

But if you're stumbling around, crashing into things. You're more than double the legal limit; it's going to be very difficult. Despite what some attorneys trying to get your money say, it's going to be very difficult to get a case dismissed under those circumstances unless you have some other angle.

Having practiced for twenty-five years, I've developed numerous defense strategies. Sometimes, individuals who weren't even driving their vehicles find themselves in these situations. There are always potential angles that can work in your favor in DUI cases in Los Angeles County.

Your best move is to consult with a DUI defense attorney who knows what they're doing and can thoroughly investigate every angle to ensure the correct result.