Probable Cause in a DUI Arrest Explained

by Douglas Kans

Probable Cause in a DUI Arrest Explained

Probable cause is a crucial component in any DUI or DWI investigation. All police officers must follow appropriate protocol when stopping a vehicle. This protocol includes having probable cause for the initial stop.

Probable cause, however, is not based on suspicion but on factual evidence. It refers to all facts and evidence that would make any reasonable individual believe that a crime has been committed, is being committed, or will be committed.

It must be noted that arresting an individual on reasonable suspicion to detain him or her for investigation is not the same as probable cause to arrest a DWI or DUI offender.

A police officer’s initial observations of a driver’s unusual behavior and driving behavior are not enough for an arrest due to probable cause, although they are sufficient in establishing reasonable suspicion for the initial traffic stop.

Probable Cause in Justifying an Arrest

Probable cause must exist and show that a crime took place and that the accused was involved or committed the criminal activity for a judge to issue a search warrant or warrant of arrest. In an arrest without a warrant such as a DUI/DWI arrest, it is important that the arrest meet the probable cause standard in order to be considered admissible in court.

At times, a DUI defense lawyer can establish that the officer arrested the driver with no probable cause. The DUI lawyer must then present the case to the trial judge, who, based on evidence, will then come to a decision. Conclusions from witnesses are not enough, as specific evidence is needed. Without proper evidence, the trial judge will dismiss the case.

Establishing Probable Cause

Often, but not always, a police officer establishes or determines probable cause to arrest a driver by the following methods:

• Observing the individual’s impaired driving behavior

• Stopping the vehicle to question the driver

• Administering a SFST or standard field sobriety test

• Administering a PBT or preliminary breath test

The DUI Arrest

Should a police officer establish reasonable suspicion and probable cause, it is highly possible that a DUI arrest will take place. Should the arrest happen, the officer must then read your implied consent rights and advise you of your right to a lawyer.

The arresting officer will then request you take a blood, urine or breath test in order to get an evidentiary chemical sample from you and determine your BAC or blood alcohol content. Refusing to take a chemical test in Minnesota is considered a crime. Should you refuse to take a certain kind of test, you must be offered another test form.

Breath Tests

Typically, the two types of breath tests are the PBT or preliminary breath test, and the EBT or evidentiary breath test.

The PBT is a handheld test used only at the scene of the stop and before a DWI arrest is made. The PBT’s sole results are not considered admissible in court, as it is not as reliable as the EBT. It simply helps officers determine whether there is probable cause to arrest the driver.

The EBT is administered at the police station after the arrest. The results of the EBT are admissible in court.

Challenging a DUI Arrest

There are many factors to consider when establishing probable cause of a DUI arrest, all the way from the time the vehicle is spotted until the DUI case is formally filed. The DUI charge can possibly be dismissed if a prosecutor is unable to establish a probable cause for a DUI arrest. It is up to the DUI lawyer to effectively challenge any flaws and mistakes that may exist during a prosecutor’s presentation of the case in court.

LOADING PDF: If there are any problems, click here to download the file.

DISCLAIMER: Because of the generality of this update, the information provided herein may not be applicable in all situations and should not be acted upon without specific legal advice based on particular situations.

© Douglas Kans, Kans Law Firm, LLC | Attorney Advertising

Written by:

Douglas Kans

Kans Law Firm, LLC on:

Readers' Choice 2017
Reporters on Deadline

"My best business intelligence, in one easy email…"

Your first step to building a free, personalized, morning email brief covering pertinent authors and topics on JD Supra:
Sign up using*

Already signed up? Log in here

*By using the service, you signify your acceptance of JD Supra's Privacy Policy.
Privacy Policy (Updated: October 8, 2015):

JD Supra provides users with access to its legal industry publishing services (the "Service") through its website (the "Website") as well as through other sources. Our policies with regard to data collection and use of personal information of users of the Service, regardless of the manner in which users access the Service, and visitors to the Website are set forth in this statement ("Policy"). By using the Service, you signify your acceptance of this Policy.

Information Collection and Use by JD Supra

JD Supra collects users' names, companies, titles, e-mail address and industry. JD Supra also tracks the pages that users visit, logs IP addresses and aggregates non-personally identifiable user data and browser type. This data is gathered using cookies and other technologies.

The information and data collected is used to authenticate users and to send notifications relating to the Service, including email alerts to which users have subscribed; to manage the Service and Website, to improve the Service and to customize the user's experience. This information is also provided to the authors of the content to give them insight into their readership and help them to improve their content, so that it is most useful for our users.

JD Supra does not sell, rent or otherwise provide your details to third parties, other than to the authors of the content on JD Supra.

If you prefer not to enable cookies, you may change your browser settings to disable cookies; however, please note that rejecting cookies while visiting the Website may result in certain parts of the Website not operating correctly or as efficiently as if cookies were allowed.

Email Choice/Opt-out

Users who opt in to receive emails may choose to no longer receive e-mail updates and newsletters by selecting the "opt-out of future email" option in the email they receive from JD Supra or in their JD Supra account management screen.


JD Supra takes reasonable precautions to insure that user information is kept private. We restrict access to user information to those individuals who reasonably need access to perform their job functions, such as our third party email service, customer service personnel and technical staff. However, please note that no method of transmitting or storing data is completely secure and we cannot guarantee the security of user information. Unauthorized entry or use, hardware or software failure, and other factors may compromise the security of user information at any time.

If you have reason to believe that your interaction with us is no longer secure, you must immediately notify us of the problem by contacting us at In the unlikely event that we believe that the security of your user information in our possession or control may have been compromised, we may seek to notify you of that development and, if so, will endeavor to do so as promptly as practicable under the circumstances.

Sharing and Disclosure of Information JD Supra Collects

Except as otherwise described in this privacy statement, JD Supra will not disclose personal information to any third party unless we believe that disclosure is necessary to: (1) comply with applicable laws; (2) respond to governmental inquiries or requests; (3) comply with valid legal process; (4) protect the rights, privacy, safety or property of JD Supra, users of the Service, Website visitors or the public; (5) permit us to pursue available remedies or limit the damages that we may sustain; and (6) enforce our Terms & Conditions of Use.

In the event there is a change in the corporate structure of JD Supra such as, but not limited to, merger, consolidation, sale, liquidation or transfer of substantial assets, JD Supra may, in its sole discretion, transfer, sell or assign information collected on and through the Service to one or more affiliated or unaffiliated third parties.

Links to Other Websites

This Website and the Service may contain links to other websites. The operator of such other websites may collect information about you, including through cookies or other technologies. If you are using the Service through the Website and link to another site, you will leave the Website and this Policy will not apply to your use of and activity on those other sites. We encourage you to read the legal notices posted on those sites, including their privacy policies. We shall have no responsibility or liability for your visitation to, and the data collection and use practices of, such other sites. This Policy applies solely to the information collected in connection with your use of this Website and does not apply to any practices conducted offline or in connection with any other websites.

Changes in Our Privacy Policy

We reserve the right to change this Policy at any time. Please refer to the date at the top of this page to determine when this Policy was last revised. Any changes to our privacy policy will become effective upon posting of the revised policy on the Website. By continuing to use the Service or Website following such changes, you will be deemed to have agreed to such changes. If you do not agree with the terms of this Policy, as it may be amended from time to time, in whole or part, please do not continue using the Service or the Website.

Contacting JD Supra

If you have any questions about this privacy statement, the practices of this site, your dealings with this Web site, or if you would like to change any of the information you have provided to us, please contact us at:

- hide
*With LinkedIn, you don't need to create a separate login to manage your free JD Supra account, and we can make suggestions based on your needs and interests. We will not post anything on LinkedIn in your name. Or, sign up using your email address.