California Supreme Court: Breathalyzer Results Can Be Challenged
An article in the Los Angeles Times late last week brought attention to the California Supreme Court’s recent ruling that Breathalyzer findings can be challenged in court:
Under the law, a suspected drunk driver can submit to either a blood test, which measures the amount of alcohol in the blood, or a breath test. Alcohol levels in a breath sample are converted mathematically to derive a blood-alcohol percentage. In California, a person is legally drunk when his or her blood-alcohol level is 0.08% or higher.
The standard formula for converting breath results to blood-alcohol levels is not accurate for everyone, however, and can vary depending on an individual’s medical condition, gender, temperature, the atmospheric pressure and the precision of the measuring device, the court said.
“The question is whether a defendant who has a blood-alcohol concentration of 0.08% or more measured by breath is entitled to rebut that presumption that he was under the influence” in certain cases, Justice Carol A. Corrigan wrote. The court’s answer was yes.
As the article explains, one of the reasons for the ruling was the potential for Breathalyzer readings that overstate the amount of alcohol in a person’s blood:
Even though experts say the standard ratio used to derive a blood-alcohol concentration from breath generally approximates or even underestimates the amount of alcohol the driver consumed, they also agree that Breathalyzer results may sometimes overestimate the amount of alcohol in the blood.
Thursday’s ruling permits defendants in some cases to challenge those results based on mathematical ratios.
“Evidence casting doubt on the accuracy of the breath-to-blood conversion ratio is just as relevant as other evidence rebutting the presumption of intoxication from a breath test result, such as evidence that the defendant had a high tolerance for alcohol or performed well in field sobriety testing,” Corrigan wrote.
Jamie L. Popper, the appellate defense lawyer in the case, had this to say:
“The situation currently is that juries are led to believe that when a person blows into the breath test, the blood-alcohol measure that breath test gives is a fact, when all a breath test is is a measure.”
For more on this topic, you can read our previous article on Breathalzyers:
It’s Just A Decimal Point: The Dirty Secret Behind Breathalyzers
And you can read the full Los Angeles Times article here.
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Since NMA is against any type of prosecutiion of drunk drivers, except if they kill someone, then what is the NMA solution to the problem? Would a solution be to have designated drunk driving hours so that the rest of us know to get off the road?
Reading is fundamental.
http://www.motorists.org/dui/
Like I said before, here is a quote from your link. Do not do anything to a a drunk driver unless he kills someone.
A “technically” impaired driver should not automatically be more heavily penalized if they are involved in an accident. The penalties should be based on the severity of the accident and the extent to which the impaired driver was at fault.
We all have known for a long time that breathalyzers are not accurate. I mean look at all the factors that go into determining the result. I mean even atmospheric pressure! I was a Meteorology major in college so i worked with a lot of electronic measuring devices and there is always error. Whether it is the machine acting up or just accepted (inherent in the device) that there is say 1% error in the data. Kinda like how radar guns are only +-2mph accurate. That means when your pulled over and a cop tells you you are doing 80 in 55 you may have been going somewhere between 78 and 82mph in actuality.
Even using a radar gun in the rain can cause even more error as the rain droplets scatter the signal!
Also to show that measuring devices aren’t accurate let’s look at a ruler. Even this has error and it’s not electronic. Let’s say the smallest markers on the ruler are 1/16th of an inch. therefore the error on the ruler is +-1/32 of an inch.
Randall get real. Your speed gun example is ignorant. Who the heck cares if a speed gun is off a couple of miles per hour if it even is. if you are clocked at 80 mph in a 55 zone and you were only actually only going 78 mph you still should be put in jail for 78 so who cares?
As for breath tests, from what I have heard they usually measure low if they are off and who cares if your blood was at .07 rather than .08? You still should not have been driving. That is why they usually do other tests that you must have failed.
What are you talking about ignorant? Being that ignorant is someone who is unknowing You used it wrong I just told you a fact, so your the ignorant one!
I was just saying that there is error. The court dosen’t care about a couple mile per hour difference.
However Laser radar guns are illegal in NJ because in the jersey supreme court ruled them innaccurate because the officer shot the laser at the wall and it came back 3mph. Now i don’t know about you but that wall is not moving at 3mph.
Shit go to jail for 80 in a 55 what state are you from? Virginia? A state of idiots reckless driving for going to fast is retarded.
In MD you don’t go to jail for simple traffic violations. I could be gong 120mph and I’m not gonna go to jail at least in the state of MD.
I’m sure your just soooo perfect randy you never break any laws anywhere whether driving or living your life. I bet you are just soooo pristine. I mean why am I arguing with someone who is sooo perfect and has no idea how electronic measuring devices work.
And why did you use the pronoun you? I have never been arrested for a dui or even accused of one so speak for yourself ass hole.
Anyways you say usually come up lower than they should. Key word: usually. Usually is not good enough in court Randy, why can’t u understand that?
Randall,
Point of clarification as a traffic officer, Radar/LIDAR instructor, and former meteorology major (Penn State ’01)… using radar in the rain does not produce “errors”, but it does decrease the effective range of the radar unit. Any readings that are returned are still accurate.
OOps, yeah your right matt. My bad on the rain and radar. I should have realized what i was saying I took radar in college.
Thanks NMA for promting drunken driving. Too many people in this world and this will help cut down the numbers.
It’s not about drunken driving Randy! It’s about your rights, your freedoms, and getting a fair trial. It’s about being able to defend yourself in court. It’s about being proven guilty beyond a reasonable doubt rather than guilty before being proved innocent.
Randall your rights as you put it are not rights but how much you want to get away with even if it is bad for society. You should not be drinking and driving but limits were set so that if you had a drink or two a few hours ago you should be legal to drive. It is not set so that you slam down a half a dozen drinks and go out and drive.
Hey Idiot! I don’t want to insult you but measuring devices have errors! What if you were actually at .06 being legal and the breathalyzer came up .09!
Therefore you were arrested wrongfully for a wrong measurement!
I’m not saying that if you blow a .26 that the breathalyzer is wrong. At that point you are beyond the error and it dosen’t matter.
But when you arrest people for blowing .08, .09 and .1 there is a chance the breathalyzer is not accurate and your being wrongfully arrested.
The government has rules to follow to when arresting you. Such as they need a reason to pull you over. They need a reason to search your car. The police officer can’t start hitting you and pulling a gun on you as your pulled over.
Oh yeah and there is the right to a fair trial and if that involves proving that an inaccurate breathalyzer is inaccurate you should be able to do that. What is wrong with you. Why don’t you move to china if you like being assumed guilty before a trial.
Like I said before you have to be proven guilty BEYOND A REASONABLE DOUBT!!!
Field sobriety tests are only about 75% accurate and if you blow a .08 you could definately prove it was wrong because there could be error there that proves you were actually under the limit. Y don’t you understand.
Your like this new employee we hired who cant remember one thing that we tell him. In one ear and out the other. But I guess in this case in one eye and out the other. you just read a select few words so you bash me about talking about rights instead of the fact that it’s about having a fair trial like I said before!
Why don’t you leave this country and go make a dictatorship somewhere because you just want to arrest anyone guilty or not.
Randall what makes you an expert at breathalyzers being 30 to 40% out of range? What policeman clocks a car that is standing still? I actually own a speed gun and know that I can not clock anything under 6 mph. It sounds to me that the judge was stupid. There are few instruments that I know of that are calibrated for measurments that far out of the normal. How accurate is your speedometer under 5 mph? I know mine is not that accurate but I bet I can tell you withiin one mph my speed when my speedometer says 55 mph. I would bet a breathalyzers may not be very accurate when there is a reading of .5 either. If breathalyzers or speed guns are that far off then I would bet they would have been outlawed everywhere. You and NMA are not for fair court judgements but are for any reason for getting out of prosecution of the laws that you break.
Is your speed gun a laser radar? Laser is different than traditional radar. Yeah your right about your speedometer, But I dont care about the speedometer, that measurement isn’t the one being used in court and how many places really have a speed limit that low to even care.
Really randy? .5? You should be dead if you blow that amount. my argument is for people who blow around .08 maybe your actually .07, Electronics can break. They are not fool proof. People who blow .12 or .25 should not be on the road and the error is not important.
You still have to go through the court process that is how our country works. Sorry Randy guilty people walk free it happens. But this is to only ensure that innocent people are not found guilty which sadly also still happens.
Randall if you are found guilty if by a very rare chance your BAC is actually only .07 but you also failed other tests then I guess you will be found DUI anyway. If you are drinking and driving and calculate your BAC should be .07 so it is safe to drive then you probably should be found guilty anyway. It has been shown that even at .05 you start to become iimpaired. If as you say the limit should be moved to .12 to allow for errors then the next person says it shoud be moved to .15 to allow for errors for the .12 reading. We have what we have and you try to not drive until your BAC is low. If you shoot a gun towards someone and miss them by a couple of inches you would be found guilty of attempted murder the same as if you hit them and they do not die.