Bay Area DUI Lawyer DMV Hearing and License Suspension

• Introduction
• DUI Stops
• Sobriety Checkpoints
• Probable Cause
• Legal Requirements
• Legal Challenges
• Field Sobriety Tests
• Chemical Testing
• Accident Investigation
• Accident Reconstruction

DUI Investigation

Driving Under the Influence (DUI), or Driving While Impaired (DWI) law enforcement investigations are commenced in several ways. A driver may be stopped for a traffic violation unrelated to DUI, such as speeding, and a DUI investigation follows. California law enforcement officers including members of the California Highway Patrol (CHP), local police officers, or sheriff's deputies may see a motorist weave between lanes, or exhibit other driving patterns consistent with a person driving under the influence. A traffic accident may initiate a drunk driving investigation and subsequent arrest, even if no one was injured. At times, all it takes is the bad luck of driving into a DUI checkpoint.

Sometimes, DUI investigations are commenced and DUI arrests follow even though police had no valid legal reason to stop the driver. An experienced California DUI defense attorney knows how to fight to suppress any evidence gathered during an illegal traffic stop that occurred without the required legal standards of reasonable suspicion or probable cause.

To lawfully initiate a driving under the influence (DUI), or driving while impaired (DWI) investigation one of three things must happen: there must be an observed violation of the law, a driving pattern so suggestive of driving under the influence of alcohol or drugs so as to provide reasonable suspicion (a legal standard) that a crime has taken place, or a lawful roadblock (also called a DUI checkpoint). If none of these conditions are present, any evidence gathered during the traffic stop may be suppressed.

California drivers sometimes are pulled over for suspicion of DUI because of driving patterns such as weaving, driving too slowly, or rapid braking or acceleration. Some of the most common reasons police stop drivers, such as speeding, aren't recognized as drunk driving patterns by the National Highway Traffic Safety Administration. An experienced California DUI lawyer with expert technical support may prove that an officer had no justifiable reason to stop the driver on suspicion of drunk driving, which may result in the suppression of any evidence gathered during the stop.

In California drivers are stopped after police receive an anonymous tip that someone is driving in a way that is suggestive of being under the influence. In the past, these DUI stops generally could not take place unless the law enforcement officer observed some independent illegal activity. However, the California Supreme Court has ruled that police can stop drivers suspected of Driving Under the Influence (DUI), or Driving While Impaired (DWI) based solely on anonymous tips.

DUI sobriety checkpoints are tools used by police to snare motorists on a number of offenses, including drunk driving. However, police don not always follow the strict guidelines the California Supreme Court has issued in Ingersoll v. Palmer that govern the establishment of sobriety checkpoints. If a DUI arrest stems from a checkpoint where police didn't follow these rules, evidence gathered during the stop may be excluded.

Driving Under the Influence (DUI), or Driving While Intoxicated (DWI) prosecutions are typically driven by four different types of evidence: driving patterns, physical signs and symptoms, field sobriety test performance, and chemical test results. The prosecutor's case is in trouble if there is an investigative failing in any of these four categories. An experienced California DUI defense attorney will uncover any holes in the prosecutor's case and use it to the driver's advantage.

California DUI arrests typically result in two separate charges - driving under the influence of alcohol, medication and/or drugs, and violating the state's Per Se laws - having a blood alcohol content (BAC) of.08 percent or greater.

Prosecutors must prove each and every element of the driving under the influence offense beyond a reasonable doubt. If there is any doubt of a DUI suspect's guilt, a jury must find the driver not guilty. To convict a motorist of driving under the influence, a prosecutor must convince a jury that the person was driving a vehicle while under the influence of alcohol or other drugs.

To convict a driver of violating California's Per Se laws (California V.C. Section 23152 - Driving Under Influence of Alcohol or Drugs), a prosecutor must prove that the driver had a BAC of .08 percent or greater while he or she was driving, not an hour or more later, when most chemical tests are conducted. An experienced California DUI attorney with expert technical support knows how to dismantle a drunk driving case, creating reasonable doubt in the minds of jurors on one or more elements of the offense in a California DUI case.

San Francisco defense lawyer Robert Tayac has defended hundreds of people accused of driving under the influence in California by convincing jurors of reasonable doubt in one or more of these critical areas.

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