The Defendant’s Guide to Probable Cause

Probable cause is a legal standard of evidence that police officers must have in order to arrest someone or obtain a warrant. If the police do not follow the probable cause requirement, you may be able to have evidence against you excluded from a court proceeding. 

What is the definition of probable cause?

The term “Probable Cause” refers to the level of certainty that police need to have in order to legally arrest someone for a crime. It is defined as enough evidence for a reasonable person to believe that the person had committed a crime, was currently committing a crime, or was about to commit a crime. To legally arrest someone, a police officer needs to have a good faith belief that the person they arrest has committed a crime. And they have to have sufficient evidence to support that belief.

What is a probable cause hearing?

The term “Probable Cause Hearing” can refer to two different types of hearings. Under Texas law, if a police officer arrests someone without a warrant, a probable cause hearing must be held within 48 hours of the arrest. During this hearing the judge will decide whether probable cause exists to support the arrest. 

The other kind of a probable cause hearing happens after the prosecution has filed charges.  Depending on the court, your attorney may have to request this hearing.  A judge will hear an explanation of the allegations and may hear testimony to determine if probable cause exists for the case to move forward. 

What is a probable cause declaration?

When a police officer applies for an arrest warrant or a search warrant, the officer will submit an affidavit or sworn statement that provides a brief summary of the facts that support a probable cause determination. 

A judge or magistrate will review this summary and decide whether probable cause exists for a warrant to be issued. In some states, such as California, the statement the police officer submits is called a probable cause declaration.  

What is an affidavit of probable cause?

In Texas, the statement a police officer must submit to justify a warrantless arrest or support a request for a warrant is called an affidavit of probable cause or a probable cause (PC) affidavit.

How does probable cause affect police from a legal standpoint?

Probable cause affects police from a legal standpoint because it defines the amount of evidence an officer must have before making a warrantless arrest. It’s also the required level of certainty for a judge to issue a search warrant or an arrest warrant. If officers don’t have enough evidence to prove probable cause, a judge might invalidate an arrest or refuse to issue a warrant.  A judge must find that there was probable cause for the officer to make a lawful arrest for the case to move forward.

What is probable cause for a DWI/DUI traffic stop?

For a police officer to pull you over to conduct a DWI or DUI traffic stop, they do not need to have probable cause that you have committed a crime. Rather, they only need to have a reasonable articulable suspicion that you have violated the law. 

Reasonable suspicion is defined as sufficient evidence for a reasonable person to suspect that a person had committed a crime or traffic offense, was currently committing a crime or traffic offense, or was about to commit a crime or traffic offense. To justify a traffic stop, the officer must have a reasonable suspicion that is more than a mere hunch. An officer must be able to point to specific, articulable facts or circumstances that created a reasonable suspicion of a violation of the law.  Officers commonly use speeding, failure to signal a lane change, or the failure to maintain a single lane of traffic as a reason to pull someone over to start conducting a DWI investigation.

People often confuse and conflate the terms “reasonable suspicion” and “probable cause.” While both are standards of evidence the police must comply with when dealing with suspects, reasonable suspicion comes a step before probable cause. When the officer thinks someone may have committed a crime, they only have reasonable suspicion. Once there is sufficient evidence that the person most likely committed a crime, the officer has probable cause.

To conduct a DWI or DUI traffic stop, the officer only needs a reasonable suspicion that you are driving while intoxicated or violating any other traffic law. However, an officer cannot arrest you for a DWI without probable cause that you were driving while intoxicated.

Is speeding probable cause for a DWI or DUI?

No. Speeding is not probable cause for a DWI arrest, but it can give rise to a reasonable suspicion to conduct a traffic stop.

The police can pull you over on a reasonable suspicion of DWI if you drive erratically or show other signs of intoxicated driving. An officer can also conduct a traffic stop based on a reasonable suspicion that you committed any traffic offense. This means that a police officer can pull you over for speeding and later arrest you on probable cause of DWI, even if they did not originally think you were intoxicated. 

For example, suppose an officer pulls you over for speeding, and you slur your speech or show other physical symptoms of drunkenness. In that case, the officer can investigate whether you are intoxicated by asking you to submit to Standard Field Sobriety Tests. If the officer is able to obtain enough evidence during the traffic stop to have probable cause that you are driving while intoxicated, you can be arrested and charged with DWI.

Do I need a criminal defense lawyer near me?

If you’ve been arrested or charged with a crime, it’s essential to consult with a criminal defense lawyer as soon as possible. An experienced attorney can review the circumstances surrounding your arrest to determine if the police followed the required probable cause standards. If the police officers violated your constitutional rights while investigating and arresting you a knowledgeable attorney can get evidence against you thrown out, and in some situations, even get your charges dismissed.

While it might seem most convenient to hire a criminal defense lawyer near you, it’s crucial that you choose an attorney who regularly defends clients in the court where you have been charged and is familiar with its practices and prosecutors.

Have questions? We protect victims like you every day.

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Read More

The Guide to Unreasonable Search and Seizure

The Guide to Texas Penal Code 12.44a

The Defendant’s Guide to Shoplifting

How to Get a Petty Theft Misdemeanor Expungement

How to Act When Stopped By Police

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