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The California DUI Stop: Probable Cause in a Nutshell

Before I begin, let me first make the following disclaimer: nothing about this article should be interpreted to mean that I somehow condone driving while intoxicated. More than 40 percent of all traffic related deaths can be directly attributed to driving while impaired. There is no question that the consequences of drunk driving can be devastating on many levels. The purpose of this article is simply to educate drivers of their rights in the event they get stopped for driving under the influence. The Fourth Amendment to the Unites States Constitution contains particular provisions to protect persons from unreasonable searches and seizure. The Supreme Court has stood firmly against police stops based on suspicion alone or even where the officer has a good reason to suspect that the driver committed or is in the process of committing a crime. This of course makes sense – police officers are suspicious by nature. One can easily make the argument that to otherwise allow a police officer to initiate a stop on a gut feeling alone would create a slippery slope and the gradual erosion of our constitutional protections. In order for a police officer to pull someone over for a DUI, the officer must have sufficient probable cause to suspect that the person is driving under the influence. This means that the officer must have a reasonable belief that the driver committed or is committing a crime. This means that the officer must have "specific and articulable facts" that, as a whole, create an inference that a crime was or is being committed. For example, the officer could have observed irregular driving patterns, such as weaving, lane straddling, or even driving significantly below the posted speed limit. More often than not, however, the driver will get stopped for a simple traffic violation such as a non-functioning taillight and the officer subsequently observes signs of intoxication. With the exception of sobriety checkpoints, which have very specific legal requirements, a police stop must be based on articulable facts that must amount to the reasonableness of the stop, even if unrelated to driving under the influence. Unfortunately, no specific benchmark exists as to what constitutes probable cause. Three teenagers driving around at 2:30 in morning in a high crime area may be trigger a suspicion that they’re up to no good. However, unless the officer can establish facts that align with the purpose for the stop, the officer may not be justified in initiating a stop, even if it later turns out that the driver is intoxicated. That being said, an officer is permitted to make a “pretext stop." A pretext stop is an objectively valid stop for an improper reason. It occurs where the police employ a stop based on probable cause or reasonable suspicion as a device to search for evidence of an unrelated offense for which probable cause is lacking. So even without sufficient probable cause to make a DUI stop, a police officer can usually find some other reason to make the stop as a pretext to investigate a DUI. In any event, the arresting officer will most likely find some basis for making the stop, which will inevitably be incorporate into the police report. Police officers know that they must incorporate enough facts to make the charges stick. And since police officers are usually not patron saints, the facts can occasionally be over exaggerated or simply fabricated to justify the stop. The arresting officer will, of course, have to substantiate the probable cause at trial, which can be challenged at trial. A side note: police officers will often ask the driver if they had anything to drink that night. Most people feel that it’s better to be honest about the drinking part and dishonest about the quantity part. This is flawed logic. There is absolutely no benefit for the driver to admit to the consumption of alcohol, regardless of quantity. If you have been arrested for DUI or simply have questions, call me at (650) 367-1771.

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