The Constitutional Law of Police Stops
When someone is driving their car on the street in California and not doing anything unlawful, the police are not legally allowed to pull them over on a traffic stop.
In other words, they are required to have “probable cause” to pull them over, which is any evidence making a reasonable person believe that a crime may have been committed or when the evidence of a crime is present in the place to be searched. Probable cause gives law enforcement officers the legal authority to pull you over.
For instance, a police officer will typically write in their report they were legally justified in pulling you over because they observed you speeding, running a red light, driving without headlights, weaving across lanes, reckless driving, or some other type of traffic law violation.
In cases where you were not committing a traffic violation, then the police officer who pulled you over might have violated your constitutional rights.
Likewise, when police pull someone over on a traffic stop and conduct roadside field sobriety tests for suspected drunk driving, they have to follow specific guidelines under the law.
Suppose the police pulled someone over who did not violate any laws or had reasonable cause and the driver was intoxicated. In that case, any evidence they seized could be found inadmissible in court. Our Los Angeles criminal defense lawyers will examine this topic in more detail below.
What Are the Rights Against Unreasonable Police Search and Seizure?
People and motorists on the highways in California have Fourth and Fourteenth Amendment rights against unreasonable police search and seizure, along with similar legal rights under California's state constitution.
The United States Supreme Court and the California Supreme Court have determined that these rights mean that law enforcement can't make a traffic stop of a motorist without having reasonable suspicion to believe that a crime is underway.
A traffic stop can be a seizure for constitutional purposes, and a police inspection of stopped vehicles can be a search for constitutional purposes.
A significant amount of federal case law helps show what police must have observed and articulated to justify a traffic stop on reasonable suspicion.
Why Does Grounds for Police Stops Matter?
The evidence and legal arguments about whether police had reasonable suspicion for a traffic stop have a lot of relevance to the outcome of driving under the influence cases.
Reasonable suspicion does matter because the exclusionary rule established in the Supreme Court case of Mapp v Ohio requires the courts to ban evidence police unlawfully gained in violation of Fourth and Fourteenth Amendment rights.
However, this exclusionary rule has a lot of exceptions. Either way, if a law enforcement officer violated your legal rights against unreasonable search and seizure by stopping you without a reasonable suspicion that justifies the traffic stop, the evidence they gathered by making the stop could be inadmissible in a court of law.
There are procedural rules in criminal cases that allow defendants to challenge their charges. A DUI lawyer could act by filing motions long before excluding evidence gained from an illegal traffic stop.
If the judge grants their motion and the prosecutor lacks other evidence to sustain the charge, the defense lawyer will often request a dismissal of the DUI charges.
Can a Prosecutor Reduce or Dismiss the DUI Charges?
A valid argument for excluding evidence from police conduct can also convince a prosecutor to reduce the charge or dismiss the case.
Traffic stops for which the police lacked reasonable suspicion put all the evidence at risk of exclusion. The derivative evidence doctrine, called the “fruit of the poisonous tree,” typically bars other evidence from the initial illegal search and seizure.
Simply put, an illegal stop can destroy a prosecutor's DUI case. Derivative evidence excluded based on insufficient grounds for a traffic stop includes the following:
- police observation of a driver's glassy eyes and slurred speech;
- police observation of open intoxicants or drugs in the car;
- field sobriety test results of the driver after the unlawful stop;
- preliminary alcohol screening (PAS) test results;
- blood-alcohol test results after the unlawful stop;
- driver confessions after the illegal traffic stop; and
- incriminating statements from witnesses inside the vehicle.
What Are Some Examples of a Reasonable Suspicion to Stop a Car?
Law enforcement officers have to typically record specific driver actions they observed to legally justify their traffic stop to investigate driving under the influence offense. A lawful police stop on reasonable suspicion follows a familiar pattern, such as: typically
- speeding over the limit or driving too fast for the conditions;
- unreasonably slow driving speed creating other driving hazards;
- driving without the use of headlights at night;
- weaving across traffic lanes in an erratic manner;
- disobeying traffic signals, such as running a red light;
- disobeying traffic signs, such as running through a stop sign,
- near-miss traffic accident due to not operating a vehicle safely;
- wrong-way driving, such as driving down a one-way street.
Are DUI Sobriety Checkpoints Legal?
Yes. A sobriety checkpoint is an exception to the Fourth and Fourteenth Amendments' reasonable suspicion requirements.
The United States Supreme Court and the California Supreme Court have determined that sobriety checkpoints are proper and legal administrative inspections even though there is no specific cause to stop drivers.
However, this does not mean there are no rules for law enforcement. The California Supreme Court has conveyed numerous requirements that sobriety checkpoints must meet. These requirements include that:
- police can't profile drivers,
- initially detain drivers for longer than a brief inspection to look for signs of intoxication.
Under California Vehicle Code 2814.2 VC, drivers must stop at adequately marked sobriety checkpoints. California's open container laws make it illegal for motorists to possess an alcoholic beverage that is opened or the seal is broken.
How Can You Fight DUI Charges?
If you are the victim of an unlawful police stop, you can fight the charges connected to the traffic stop. If we can show the traffic stop was unjustified, any seized evidence could be deemed inadmissible in court.
Depending on the details of the case, we might be able to uncover the truth in the police stop that led to your DUI arrest. We will also examine the field sobriety test and breath or blood tests administered after the traffic pullover.
If you were arrested at a sobriety checkpoint, we would examine whether it was set up correctly and lawfully. Law enforcement officers must follow specific rules. If they fail to follow the procedures, your charges might be dismissed.
Regardless of the details of your California Vehicle Code 23152 VC DUI charges, whether it's a first-time misdemeanor DUI, a felony DUI, or VC 23153 DUI causing injury, our defense lawyers can help you.
We can also protect your driver's license at the DMV hearing, which must be requested within ten days of your arrest. Eisner Gorin LLP is based in Los Angeles County, and you can contact us for an initial consultation at (877) 781-1570 or fill out the contact form.
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