DUI Driving Defenses

The first thing a prosecutor must prove in a DUI case is that “the defendant drove a vehicle.” If the prosecutor can’t prove beyond a reasonable doubt that you drove the vehicle, then the jury can’t convict.  The best defense to a DUI charge is that you were not driving.    

Identity of Driver

The government has to prove you were the driver of the vehicle. If you were behind the wheel when the police pulled you over, it’s easy for them to prove you were the driver. It’s more difficult to prove who the driver was in cases where there is an accident, the car is abandoned or parked, or someone called 911. The government will try to prove you were the driver through circumstantial evidence like the car being registered to you, if you have the keys, the car is still warm, witness statements, your proximity to the car, if no one else is around, and if you admit to driving. The best defense to a DUI is if you weren’t the driver.

Time of Driving – DMV Hearing

Time of driving is important in a DMV hearing because for the DMV to take action against you they have to prove that the breath or blood test was taken within 3 hours of driving.  This usually is an issue in accident cases, sleeping in car cases, or 911 cases.  In these type of cases, police usually arrive at some time after the alleged DUI driving occurred.  If the DMV can’t prove driving occurred within 3 hours of the breath or blood test, you should win the DMV hearing because for the breath or blood test result to be admissible at the DMV hearing it has to be taken within 3 hours of driving.        

Time of Driving – Court Case

Time of driving is important in a DUI case because to be convicted you have to be impaired or over a 0.08 percent alcohol at the time of driving.  This usually is an issue in accident cases, sleeping in car cases, or 911 cases.  In these type of cases, police usually arrive at some time after the alleged DUI driving occurred.  The longer time has gone by between the chemical test and the time of driving makes it difficult for the prosecution to justify the chemical test result because they have to resort to retrograde extrapolation to determine the actual alcohol level at the time of driving.  Retrograde extrapolation has been determined by most scientists to be inaccurate and should not be used to determine prior alcohol concentrations.         

volitional Movement of the Vehicle

Section 23152 requires proof of volitional movement of a vehicle.  This means that the vehicle has to actually move.  The amount of movement can be slight and can be proved with circumstantial evidence.      

Bad Driving Not enough to prove DUI 

The manner in which a person drives is not enough by itself to establish whether the person is or is not under the influence of an alcoholic beverage or drug. However, it is a factor to be considered, in light of all the surrounding circumstances, in deciding whether the person was under the influence.