Review of the Constitutional Law of Police Stops
When you are driving on a street or highway in California and not doing anything unlawful, then law enforcement officers can't just pull you over on a traffic stop for no reason.
In any type of police traffic stop, they are legally required to have probable cause to pull you over. So, what exactly is “probable cause?”
In the context of our criminal justice system, probable cause is essentially any evidence that would make a reasonable person believe that a crime may have been committed or when evidence of a crime is present in the place to be searched.
Put simply, probable cause gives the police the legal authority to pull you over.
For example, the police officer will normally write in their report they were justified in pulling someone over because they were speeding, ran a red light, driving without headlights, excessive braking, weaving, reckless driving, or some other traffic law violation.
If this was not true, however, then the police officer who pulled you over might have violated your constitutional rights.
In order to pull a driver over on a traffic stop and conduct roadside field sobriety test for suspected drunk driving, police officers have to follow specific guidelines under law.
As noted, police are required to have probable cause to pull over a vehicle driven by a suspected drunk driver.
When they pull somebody over who has not violated any laws or given them reasonable cause they are intoxicated, then any evidence they seize could be found inadmissible in court.
Our Los Angeles criminal defense lawyers will review the laws more closely below.
Rights Against Unreasonable Police Search and Seizure
Individuals, including motorists on California's highways, have Fourth and Fourteenth Amendment rights against unreasonable police search and seizure. They also have similar rights under California's state constitution.
The United States Supreme Court and California Supreme Court have interpreted those rights to mean that police may not make a traffic stop of a motorist without reasonable suspicion to believe that a crime is underway.
Traffic stops can be seizures for constitutional purposes. Police inspections of stopped vehicles can be searches for constitutional purposes.
Substantial federal case law helps to show what police must have observed and must be able to articulate to justify a traffic stop on reasonable suspicion.
Why Grounds for Police Stops Matter
Evidence and legal arguments over whether police had reasonable suspicion to make a traffic stop matter to the outcome of DUI cases.
Reasonable suspicion matters because the exclusionary rule established in the Supreme Court's case Mapp v Ohio generally requires that courts bar evidence that police gained illegally in violation of Fourth and Fourteenth Amendment rights.
The exclusionary rule has many details and exceptions. But if police violated your rights against unreasonable search and seizure by stopping your vehicle without reasonable suspicion justifying the stop, then DUI crime evidence the police gained by making the stop may be inadmissible.
Motions to Exclude Illegally Gained Evidence
Procedural rules in criminal cases give a DUI defendant a way to enforce those rights and beat the charges.
A skilled defense attorney would move well before trial to exclude evidence gained from an illegal stop.
If the trial judge grants the motion, and the prosecutor has insufficient other evidence to sustain the charge, as is commonly the case, defense counsel would move for dismissal of the DUI charges.
Courts often order such dismissals after granting a motion to exclude if the prosecution hasn't already agreed to dismiss the case.
Reduced or Dismissed Charges
A strong argument for excluding evidence from suspect police action can also influence a cautious prosecutor to reduce the charge or dismiss the case.
An initial traffic stop for which the police lacked reasonable suspicion puts at risk all following evidence.
The derivative evidence doctrine, also known as the fruit of the poisonous tree doctrine, ordinarily bars other evidence derived from the initial illegal search and seizure.
In other words, an illegal stop can gut a prosecutor's DUI case. Derivative evidence excluded due to insufficient grounds for a traffic stop can include:
- the officer's observation of the driver's glassy eyes and slurred speech;
- the officer's observation of open intoxicants or drugs in the vehicle;
- field sobriety test results of the driver following the illegal stop;
- preliminary alcohol screening (PAS) test results after the stop;
- blood-alcohol test results after the illegal stop;
- driver confessions and admissions following the illegal stop; and
- incriminating statements from passenger witnesses within the vehicle.
Examples of Reasonable Suspicion to Stop
Police must generally record and recall specific observable driver actions or omissions to justify their traffic stop to investigate DUI crime.
Lawful police stop on reasonable suspicion tend to follow these and similar patterns:
- lane violations, especially repeated wandering or weaving across lines;
- unnecessary lane changes when conditions do not recommend them;
- excessive speed over the limit or unreasonable for existing conditions;
- unreasonably slow speed creating other driving hazards;
- failure to adjust speed, such as going fast in slow and slow in fast lanes;
- wrong-way driving down one-way streets;
- disobeying traffic signs and lights such as running stop signs or red lights;
- near-miss accidents, especially those avoided by other drivers;
- frequent braking or riding the brake when conditions do not warrant it;
- u-turns and illegal turns against traffic laws or in unsafe conditions; and
- vehicle anomalies like lights out after dark or tops down in cold or rain.
Sobriety checkpoints are exceptions to the Fourth and Fourteenth Amendment's reasonable suspicion requirement.
The U.S. Supreme Court and the California Supreme Court have both held that sobriety checkpoints are permissible administrative inspections even without specific cause to inquire of stopped drivers.
The California Supreme Court, though, has articulated several requirements that sobriety checkpoints must meet.
Those requirements include that the police not profile drivers or initially detain them for more than a brief inspection to look for signs of intoxication. California Vehicle Code 2814.2 VC requires drivers to stop at adequately marked sobriety checkpoints.
Defense of DUI Charges in California
When you are facing an unjustifiable police stop, then you have the right to fight the charges connected to the traffic stop.
If we can show the traffic stop was unjustified, any DUI evidence against you can't be allowed admissible in court.
Our law firm may be able to uncover the truth in the police stop that led to your driving under the influence arrest.
We will closely examine the field sobriety test and any breath or blood tests that were administered after you were pulled over.
If you were arrested at a DUI sobriety checkpoint, then we can review whether it was set up lawfully.
At checkpoints, law enforcement officers are required to follow specific rules. If they fail to follow proper procedures, then any criminal charges could be dismissed.
In spite of the circumstances of your California Vehicle Code 23152 DUI charge, whether it's a first-time DUI, multiple DUI charge, felony DUI, charges of DUI causing an injury, our criminal defense lawyers can help you.
We also know how to protect your driver's license at your DMV hearing, which must occur within ten days of your arrest.
Eisner Gorin LLP is located in Los Angeles County and you can contact our office for an initial consultation at (310) 328-3776.