Things To Know When Facing A DUI Trial: Permissive Inference
One of the most important legal concepts that can significantly impact your DUI case is “permissive inference.” This tool allows the prosecution to present evidence about your blood alcohol content (BAC) in a way that can influence the jury’s decision. If you’re preparing for a DUI trial, knowing how permissive inference works, when it applies, and how it can be challenged could make the difference between conviction and acquittal.
Our experienced criminal defense attorneys at Wallin & Klarich can guide you through the legal process. Call Wallin & Klarich today toll-free at (877) 466-5245 for your free consultation with one of our appeals attorneys near you.
Understanding Permissive Inference in DUI Cases
Permissive inference is a legal concept that allows a jury to draw certain conclusions from evidence, but doesn’t require them to do so. In DUI cases, this relates specifically to how chemical test results showing your blood alcohol level can be used to infer whether you were under the influence at the time you were actually driving.
The key distinction here is between what the law calls “rebuttable presumptions” and “permissive inferences.” While they may sound similar, they have very different implications for your constitutional rights and how a jury can consider the evidence against you.
Vehicle Code Sections 23152(a) and 23152(b)
California Vehicle Code provides the framework for how blood alcohol evidence can be used in DUI prosecutions. Under Vehicle Code Section 23152(a), the prosecution must prove you were under the influence while driving. Under Section 23152(b), they must prove you had a blood alcohol level of 0.08% or more while driving.
The statutes establish that chemical analysis results showing the amount of alcohol in your blood or breath can “give rise to a rebuttable presumption” about whether you were under the influence at the time of the offense. Vehicle Code Section 23610(a)(3) specifically creates a rebuttable presumption that if your blood alcohol level was 0.08% or more at the time of chemical analysis, then you were under the influence at the time of driving.
For Vehicle Code Section 23152(b) violations, there’s an additional rebuttable presumption: if you had a blood alcohol level of 0.08% or more at the time of the chemical test performed within three hours after driving, the law presumes you had that same level while actually driving.
Why Courts Use Permissive Inference Instead of Rebuttable Presumptions
Because rebuttable presumptions can potentially violate a defendant’s constitutional rights, California courts have determined that jury instructions should frame these statutory presumptions as “permissive inferences” instead.
The California Court of Appeal addressed this important distinction in People v. Beltran (2007), explaining the difference between “rebuttable presumptions” and “permissive inferences.” The court recognized that presumptions can raise constitutional concerns, so jury instructions are crafted to give juries permission to draw inferences from the evidence rather than directing them to presume certain facts.
The critical language is “you may, but are not required to” draw these conclusions. This gives juries the option to consider the chemical test results as evidence of intoxication at the time of driving, but it doesn’t force them to reach that conclusion.
Defense Strategies for Challenging Permissive Inference
Understanding permissive inference opens up several potential defense strategies:
Challenging the Sufficiency of Evidence: If the prosecution cannot establish substantial evidence that your BAC was at or above 0.08% at the time of testing, you may be able to prevent the jury from receiving these inference instructions altogether.
Presenting Alternative Evidence: Since these are only permissive inferences, presenting strong alternative evidence about your actual impairment level, rising blood alcohol, or testing errors can give the jury reasons not to draw the inferences suggested by the instructions.
Attacking Test Reliability: Challenging the accuracy, calibration, or proper administration of chemical tests can undermine the foundation for permissive inference instructions.
Expert Testimony: Forensic toxicology experts can explain to juries why they shouldn’t draw inferences from chemical test results, particularly when there are issues with testing procedures, equipment, or biological factors affecting alcohol absorption and elimination.
Contact Wallin & Klarich Today
If you are facing DUI charges, you need to contact an aggressive defense attorney to fight for your freedom. With 40+ years of experience, our attorneys at Wallin & Klarich have helped many clients ensure they receive a fair trial in their criminal defense cases. We know the most effective strategies to argue on your behalf, and we will do everything in our power to help you achieve the best possible result in your case.
At Wallin & Klarich, we have offices all over Southern California: Irvine, Pasadena, Riverside, San Bernardino, San Diego, Torrance, Victorville, and Anaheim. Additionally, our law firm can handle many types of cases statewide.
Discover how our team can assist you. Contact us today, toll-free at (877) 466-5245 for a free consultation with a skilled defense attorney near you.
