This is a very common calculation in a DUI case because one of the main issues is, what was a driver’s blood alcohol concentration (BAC) at the actual time of driving? In a typical case, a police officer has the driver participate in a chemical test, generally a breath test or a blood test, which gives an estimate of the driver’s BAC at the time of the test. The state’s expert then has to engage in a process entitled “Retrograde Extrapolation”. This is a formula and mathematical calculation that is made to theoretically estimate what the blood alcohol concentration was at the time of driving. It is a calculation backwards in time from the time of the test to the time of the driving.

A common defense in a DUI case is that although the driver may have been at .08% or higher at the time of the test, the mathematical calculation backwards or Retrograde Extrapolation may or may not establish that the driver was actually under the legal limit when driving. These calculations are very complicated, have been called into question by many scientific experts and involve a number of different factors. The defense will generally establish that that variables included in the calculations are unknown and therefore the person who makes the calculation has to make a variety of assumptions which may or may not be true. There are numerous studies that attack the validity of the Retrograde Extrapolation process.

Problems with BAC tests.

One of the problems with this Retrograde Extrapolation process is that police officers almost always use only a single test with two numerical results that are acquired within two to four minutes of each other. The failure to take another test 30 to 45 minutes later often puts the experts in the untenable position of not being able to determine whether the BAC was on the rise or in decline. Some of the variables that are difficult to establish in this Retrograde Extrapolation calculation are the rate of absorption of alcohol into the blood and the rate of disappearance or elimination of alcohol from the blood. Because these rates are unknown, an expert who testifies for the prosecution will always use the estimated average rate of the general population which may have no basis in reality for a particular defendant. The computation or formula used by forensic experts to make these calculations is referred to as the Widmark Equation. The Equation is used to estimate either the number of drinks that a defendant consumed and/or the corresponding blood or breath alcohol concentration at a specific point in time.

Variables in alcohol absorption.

There are generally about seven different random variables that are unknown and yet are assumed by the expert. As an example, one of the variables that are completely unknown, as to any particular individual, is the rate of absorption or the time that it takes for alcohol to reach the brain. This rate of absorption can vary greatly. Alcohol can be absorbed into an individual’s bloodstream as quickly as 30 minutes and as long as six hours after consumption. In addition to this problem, there always exists the possibility of short term fluctuations of blood alcohol concentrations in any particular person at any particular time. This short term fluctuation alone can interfere with any sense of precision in using the Widmark Equation. These are all factors that a Mendocino DUI attorney will point out and use to defend a DUI case.

For more information about California DUI issues, click here.

Well, that depends! This is one of the most commonly asked questions and a commonly used excuse by police to stop vehicles. If you do an informal survey by simply watching other cars in California, you’ll notice that approximately one in ten do not have an actual license plates on the front of the car. California DMV typically issues two license plates for each motor vehicles (other than motorcycles) and Vehicle Code §5200(a) requires two license plates to be attached to your vehicle. So, the absence of a front license plate in California is an established and accepted basis for a traffic stop.

What about out-of-state drivers?

But wait, if a person is driving a car that is registered in another state and has out-of-state license plates and the police officer does not know whether or not that state requires one or two license plates, the absence of two license plates is not a constitutional basis to stop a vehicle. In the case of People v. Reyes, (2011) 196 Cal.App.4^th 856, the Sixth District Court of Appeal reversed the trial court’s decision and granted a motion to suppress (preventing the evidence from being used in court) eliminating most of the harmful evidence that was discovered by the police after the stop, which included a bag of cocaine. This is what a Santa Rosa criminal defense attorney refers to as a “mistake of law”.

Police officer’s mistake of law

In the case of U.S. v. Twilley, (2000) 22 F.3d 1092, 1095, the Ninth Circuit held that a mistake of law does not provide an objectively reasonable basis for a police officer to stop a vehicle. In that particular case, the vehicle displayed only one Michigan license plate, but since the officer did not know the law in Michigan, he mistakenly assumed the vehicle required two license plates. In short, if an officer makes a traffic stop based on a mistake of law, that stop violates the Fourth Amendment and evidence acquired as a result of that unconstitutional stop will be thrown out of court. Most states do require two plates but there are 19 states (or approximately 40% of the states) that currently only require one plate.

Further, in People v. White, (2003) 107 Cal.App.4^th 636, 641, a Fourth Appellate District decision, the officer observed a vehicle with only one Arizona license plate and as a result, stopped the vehicle. Just like Michigan and Florida, Arizona only requires one license plate. The court ruled that a police officer’s suspicion which is based on a mistake of law cannot constitute a constitutional basis to justify a legal traffic stop.

Ambiguity means the vehicle should not be stopped.

As noted by a Santa Rosa criminal defense lawyer, as to an out-of-state vehicle, if a police officer does not know whether one or two license plates are required that ambiguity prevents the police officer from stopping the vehicle. Otherwise, police officers could rely on their ignorance of the law and that would provide a strong incentive for police officers to pull an out-of-state vehicle over in all circumstances. “Ignorance of the law” is no excuse for citizens or police officers who are entrusted to enforce the law. For more information about California search and seizure issues, click here.

Relief from Misdemeanor Sex Offender Registration Before 1995

Penal Code §1203.4, which is commonly referred to as the law that allows for dismissal of convictions or expungements, permits, if not mandates, the court to vacate and dismiss a conviction upon successful completion of probation. Prior to 1995, the law allowed the cancellation of sex offender registration for misdemeanor sex offenders if they successfully applied for and received a dismissal or expungement.

After 1995

On January 1, 1995, the law changed and, as a result, nobody is relieved from the duty to register by acquiring an expungement pursuant to Penal Code §1203.4. However, even today, if a person has a conviction for certain a misdemeanor sex offenses that occurred prior to 1995, the Department of Justice will terminate mandatory registration. After January 1, 1995, as noted by a Lake County criminal attorney, misdemeanor sex offender registration can only be relieved or canceled through the acquisition of a Certificate of Rehabilitation.

Termination of Sex Offender Registration in Felony Cases

As far as felony sex offense registration is concerned, the statutes and case decisions interpreting those statutes are much more convoluted and will be the subject of another blog. Clearly, anyone who suffers from mandatory registration as a sex offender should be contacting a criminal defense attorney to have their criminal history analyzed to determine if, and, when, they can terminate their PC §290 sex offender registration.

Fore more information about California expungements or a Certificate of Rehabilitation, click here.

Recently, Division 1 of the Second District Court of Appeals, in a case entitled People v. Pellecer, ruled that carrying knives in a backpack does not violate Penal Code §12020(a)(4) which is a law that makes the carrying of a concealed knife on your person criminal. That particular statute or law requires that the knife be concealed on an individual’s “person”. As noted by a Eureka criminal defense attorney, that statute should be strictly construed or interpreted.

At trial, the defendant argued that when he was found by the police he was leaning on his backpack. In the court’s instructions to the jury at trial, the court indicated that the statutory language “on his person” would include “a bag or container carried by the person”. The defendant made the argument that if the statute requires knives to be carried on their person, it means exactly that. If knives were carried in some type of a container such as a backpack or suitcase, that situation would not be one that was anticipated by the statute or criminal law.

The Court of Appeal agreed and the decision by the trial court, convicting the defendant, was reversed. The court ruled that former Penal Code §12020(a)(4) provided criminal penalties for someone who was carrying a knife on their person and that a dirk or a dagger carried inside a container such as a backpack or a suitcase does not fall within the language of the statute and, therefore, the defendant was not guilty. This is a decision based on a principle that has been long argued by Eureka criminal defense lawyers. The court is required to look at not only the legislative history of a statute but also its “plain reading”. The legislature could have very easily, when it enacted the statute, added the language “or in a container carried by the individual”.

For more information about California criminal assault issues, click here.