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Probable Cause for Drunk Driving Defined in Los Angeles

In an attempt to curb road accidents, a traffic police officer has the authority to point out your vehicle to pull over for an investigation if they suspect that you are drunk driving. However, they must have reasonable suspicion and probable cause to do so lawfully without violating your constitutional rights.

"Reasonable suspicion" and "probable cause" are vital terms in a drunk driving case which you ought to understand if you are under arrest for an alleged drunk driving case. To better understand these terms and how they can affect the alleged drunk driving charge, you should contact an attorney for legal guidance and representation henceforth.

Arguing that the arresting officer did not have probable cause to stop your vehicle or arrest you on suspicion that you are drunk driving is one of the strongest defenses your attorney can apply for the best possible outcome. Experienced attorneys at Jonathan Franklin DUI Attorney are here to help if you are in trouble with the law for an alleged drunk driving charge in Los Angeles, Ca.

If your friend is in custody for a drunk driving case, or perhaps you are just curious to know how to fight a drunk charge, you are in the right place. This article will help you understand what counts as probable cause in a drunk driving case and how your attorney can challenge it for the best possible results on your case.

Probable Cause Versus Reasonable Suspicion in Drunk Driving Cases

According to the fourth amendment of the constitution, a law enforcement officer has no authority to make a traffic stop, investigation, or arrest without a certain level of justification to believe you are a suspect in a crime.

In the context of a drunk driving case, law enforcement officers must have reasonable suspicion before initiating a traffic stop and probable cause before making an arrest. Typically, "reasonable suspicion" and "probable cause" are two different standards in a drunk driving case. The prosecutor can use these legal terms interchangeably to show the traffic stop, and your arrest was lawful to secure a conviction against you for drunk driving.

Since the constitution's fourth amendment protects you from unreasonable searches, a police officer cannot select your vehicle to pull over for an investigation without a reasonable suspicion to believe that you are a suspect in a crime. To show the court that there was a reasonable suspicion to believe you were drunk driving before the traffic stop, the officer may argue that:

  • You were driving erratically with frequent braking
  • You were speeding
  • You were drifting from one lane to the other
  • There was an illegal turn

Even if you were drunk driving at the time of the arrest, the court might dismiss your charge if your attorney can prove that the traffic stop was due to innocent reasons like your race, skin color, or car type.

Typically, reasonable suspicion allows a traffic police officer to stop and detain you for a short period. However, to arrest you on suspicion that you were drunk driving, a police officer must have a higher standard of justification or "probable cause" to make your arrest lawful.

That means the arresting officer must be ready to establish particular facts in court to show why they believed that you were drunk driving.

Facts that Count as Probable Cause in a Drunk Driving Case

Typically, the prosecutor presiding over your case will need the arresting officer's evidence when building a drunk driving case against you. Vehicle Code (VC) 23152 (a) is the statute that explains what the prosecutor needs to prove to secure a conviction against you for drunk driving. To help the prosecutor prove that you were drunk driving, the arresting officer should specifically explain to the court the reasons for the traffic stop and the circumstances of your arrest.

Typically, a law enforcement officer needs more than a hunch or mere suspicion that you were drunk driving before initiating an arrest during a stop at a sobriety checkpoint for an alleged VC 23152 (a) violation. That means having slurred speech or watery eyes is not enough to justify the existence of probable cause for your arrest.

Explained below are some facts or evidence that the arresting officer may raise in court to justify probable cause for the arrest on suspicion that you were drunk driving:

Poor Performance on the Field Sobriety Tests (FSTs)

The prosecutor will rely heavily on your performance on various FSTs to prove that you were drunk driving. Typically, FSTs are a series of physical tests the traffic officer will use to gauge your sobriety after a traffic stop, including:

  • Walk and turn test
  • One-legged stand test
  • Horizontal gaze nystagmus test

The above standard FSTs help an officer observe your balance, attention level, and physical ability to drive a vehicle as a typical sober driver would. To justify the existence of probable cause for your arrest, the officer will say your performance results on the above FSTs were poor, meaning that your blood alcohol content (BAC) was most likely above the legal limit.

Your Breath Test Results Were High

In an attempt to gather more probable cause to justify your arrest was lawful, the officer will also require you to take a preliminary breath test which involves blowing a breathalyzer. A breathalyzer is special hand-held equipment that uses your breath vapor to determine whether or not your BAC level is above the legal limit.

Typically, if your BAC level is 0.08% or above, the officer will consider you impaired, meaning you cannot drive a vehicle like a cautious sober driver. In this situation, your breath test results will be enough to justify probable cause for your arrest during prosecution for allegedly driving a vehicle while under the influence of alcohol.

You Did Exhibit Distinct Physical or Objective Signs of Intoxication

After stopping your vehicle for a quick investigation at a sobriety checkpoint, the officer will also pay attention to see whether or not you exhibit particular objective signs of intoxication or impairment, for example:

  • Slurred speech
  • Watery eyes
  • Bloodshot eyes
  • Alcohol odor from your breath
  • Dilated pupils

Generally, the above physical signs of intoxication will count as probable cause for your arrest on suspicion that you were drunk driving. If the arresting officer's report does not contain these crucial pieces of evidence to justify the existence of probable cause for your arrest, the court may consider the arrest wrongful.

Determining if There Was Probable Cause for Your Arrest for the Alleged Drunk Driving Charge

Unfortunately, an unlawful arrest may lead to a wrongful conviction if the prosecutor can prove beyond a reasonable doubt that your arrest was lawful and your BAC was above the legal limit. To determine whether or not the arresting officer had probable cause to initiate your arrest, you should seek an attorney's legal assistance.

Once you contact an attorney, they will request a copy of the arresting officer report and begin the investigation there to know whether or not your arrest was lawful. Apart from contacting an attorney, it would help if you did the following to preserve your best interests after a traffic stop on suspicion that you were drunk driving:

  • Stay calm and focused
  • Don't answer the officer's trick questions (remain silent)
  • Resist a warrantless or illegal search in your car

Challenging Probable Cause for Your Arrest on Suspicion That You Were Drunk Driving

If your attorney believes that the arresting officer did not have a reason or probable cause to arrest you for the alleged drunk driving charge, they will help you seek dismissal or acquittal of the case. To challenge probable cause for your arrest on suspicion that you were drunk driving, your attorney will request a suppression hearing under section 1538.5 of the Penal Code (PC).

Typically, your arrest for the alleged drunk driving charge will be unlawful if the arresting officer did not have reasonable suspicion to conduct a traffic stop or probable cause to initiate the arrest. Under this statute, the court will suppress all the pieces of evidence the officer has against you for drunk driving if your attorney can prove beyond a reasonable doubt that your arrest was unlawful.

For instance, if the officer seized evidence from your car without a search warrant, the court will consider it inadmissible, meaning the prosecutor cannot apply it against you. Although a motion to suppress evidence under PC 1538.5 is not always successful in drunk driving cases, your attorney will request it as a defense strategy to counter the alleged drunk driving charge.

Filing a petition to suppress evidence is an important part of the pretrial process because it allows your attorney to cross-examine the strength of the prosecutor's drunk driving case against you to point out its weaknesses. If everything goes well on your petition, the court may dismiss or reduce the alleged drunk driving charge to a less severe related offense like reckless driving.

What to Expect if a Suppression Hearing Under PC 1538.5 is Unsuccessful

Unfortunately, if it is impossible to challenge the probable cause for your arrest under PC 1538.5, your drunk driving case will move to the next stage of the prosecution process, the trial. When that happens, your attorney will begin preparing viable evidence to counter the alleged drunk driving charge because the outcome of the trial hearing can lead to life-changing consequences.

The court will expect the prosecutor and your attorney to demonstrate their evidence on the alleged drunk driving charge beyond a reasonable doubt at the trial hearing. Below are some of the applicable defense arguments your defense attorney may apply to counter the alleged drunk driving charge for the best possible outcome:

Bad Driving is Not an Accurate Indicator of Alcohol Intoxication

To secure a conviction against you for VC 23152 (a) violation, the prosecutor must show the court that you were under the influence of alcohol at the time of the arrest. When the prosecutor uses the arresting officer's testimony about your driving pattern to prove that you were drunk driving, your attorney can argue that your driving pattern was not due to alcohol intoxication.

The court may consider this argument reasonable because even a sober and cautious driver can swerve or make an unsafe left turn.

Objective/Physical Signs of Intoxication is not an Accurate Indicator of Alcohol Intoxication

Another way to fight a drunk driving charge is by challenging the prosecutor's application of physical signs of intoxication at the time of the arrest to show that you were under the influence of alcohol. Although objective or physical signs of intoxication may count as an indicator of alcohol intoxication, exhibiting these signs might also be due to innocent reasons, like fatigue, cold, or allergies.

Your Performance Results on FSTs are Not Due to Alcohol Intoxication

Although a driver's performance on FSTs may show whether or not they are under the influence of alcohol, these tests are not accurate because even a sober person can perform poorly on them due to the following innocent reasons:

  • Inadequate lighting
  • Nonuniform ground level
  • An injury on the leg
  • Improper instructions by the officer
  • Improper clothing or shoes

Your BAC Test Results Were Inaccurate

Arguing that your BAC test results were inaccurate is an applicable and viable legal defense in a drunk driving case. The court would consider this defense argument reasonable if your attorney can prove that your BAC test results were high due to other reasons unrelated to alcohol drinking and impairment, for example:

  • The breathalyzer equipment was faulty
  • Residue mouth alcohol

If these defense arguments are viable, the court may dismiss or reduce the alleged drunk driving charge to a less severe offense like dry reckless, which carries less severe penalties than the initial charge.

Find a Los Angeles DUI Attorney Near Me

Since probable cause determinations cover a very intricate and confusing area of the law, you should have an attorney on your corner if you are under arrest for an alleged drunk driving charge.

We at Jonathan Franklin DUI Attorney can help you determine whether or not your arrest for the drunk driving charge was lawful. Our skilled attorneys have what it takes to challenge probable cause for your arrest on suspicion that you were drunk driving for a less severe charge or dismissal of the case.

We invite you to call us at 323-464-6700 if you are under arrest for an alleged drunk driving charge in Los Angeles, California, to discuss your case with our attorneys for immediate help that you need.

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Jonathan Franklin DUI Attorney
6777 Hollywood Blvd Ste 508
Los Angeles, CA 90028
323-464-6700