DUI Defense: Attacking the breath test in Los Angeles DUI Prosecution
Many police officers consider all traffic stops a DUI investigation. Thus, the second you are stopped in Los Angeles by a police officer, you are suspected of a DUI! This is more so after accidents in Los Angeles, Orange County, etc. For example, if you are stopped for not wearing a seatbelt, many police officers, CHP officers, or any other law enforcement officer, will note if you can be under the influence of alcohol or drugs. They are trained to detect any signs of alcohol consumption, such as open bottles, the smell of alcohol, and any other signs, such as red eyes and slurred speech. Drunk driving attorneys in Los Angeles specialize in defending people who are pulled over without a good reason. Los Angeles DUI attorneys will fight these cases by filing motions to suppress evidence. But even if police can come up with a good reason for the stop, a Los Angeles DUI attorney can fight your case at trial by trying to show that the DUI breath test was not accurate.
To prosecute a DUI in Los Angeles, the prosecutor needs to show impairment at the time of driving. Because tests for alcohol are measured much after the stop, the prosecutor has to present evidence of the BAC level at the time of driving. This is done through a formula created in the 1920th by Swedish professor Erik Windmark. The formula is BAC = 100*A/(r* W) – B*t.
A = mass of alcohol consumed ( a drink is assumed to contain 10-14 grams of ETOH)
r = ratio of body water to alcohol and is assumed .68 for men and .55 for women.
W = body weight
b = rate of alcohol metabolism and is assumed to be .017 per hour.
t = time alcohol present in the body.
EXAMPLE: To calculate his BAC at the time of driving we need to know, how much alcohol was consumed, what time the person started to drink, if it is a male or female, and how much that person weighs. The BAC levels for a 120 lb female will be much different than for a 200 lb male. Let’s assume, this person drinks 2 drinks (.02 kg), is a female (.55), weighs 120 lb (54 kg), and consumed alcohol two hours before stopping (.017 x 2). Then the BAC level at the time of driving will be estimated to be 100*.02/.55*54 – .017 *2 = .067-.034 = .033 BAC.
Los Angles DUI prosecutors usually use Windmark’s formula in a different way. Instead of determining the level of alcohol at a certain time, they modify the formula by solving it for the number of drinks consumed. Typically, during a trial, Los Angeles DUI prosecutor asks his toxicology expert if he is able to determine the number of drinks a person had based on the level of alcohol presented. This can be easily calculated using Windmark’s formula by plugging in the weight, gender, and time after driving. The modified formula would then turn into A = (BAC+B*t) * (r* W)/100
For example, if a hypothetical 175 lb male is .10 % BAC 1 hour after driving, Los Angeles DUI prosecutor asks his expert to use the Windmark formula to estimate the number of drinks in that person’s body. The BAC, 1 hour prior to testing (at the time of driving) would be .117 % BAC. Next, Windmark must adjust for body weight and the ratio of water to weight (79kg and .68 for man), to wit 53.72, and multiply by this number to get to 6 drinks.
If you were arrested for a DUI in Los Angeles, you were asked to give a sample of your blood or breath. If you agreed to provide a breath sample, you were probably taken to a police station where you blew into a machine to measure your blood alcohol level. There are several machines used by different police agencies in Los Angeles County. These machines sometimes use infrared light or sometimes use fuel cell technology (making electricity) to measure the amount of alcohol in a person’s breath.
The breath machines are not accurate and have a margin of error that can be as high as .02% in some DUI breath tests. That means that a .08% blood alcohol level can lower by .02%, equal to.06% because the alcohol testing machines are very inaccurate. The prosecutor can argue that your blood alcohol level can be higher by .02%, but all evidence that can be helpful or hurtful to you must be used to help you. Armed with law and science, Los Angeles DUI attorneys can win your Los Angeles DUI in court.
Attorneys in our office can show to the jury that breath alcohol machines can give wrong results on your DUI breath test and that having a .08% BAC in your breath is not correctly measured.
Please call Los Angeles DUI Attorney at 323-464-6424 so we can help you fight your Los Angeles DUI case!