What Happens at DUI Checkpoints in Missouri?

When a driver on a Missouri highway notices flashing lights, patrol vehicles, and traffic slowing to a stop ahead, that driver may be approaching a DUI checkpoint. These temporary roadblocks raise immediate questions: What happens at DUI checkpoints? Are DUI checkpoints legal in Missouri? Does someone have to stop at DUI checkpoints?

At Rose Legal Services, we dedicate our practice exclusively to criminal defense. We represent people facing Driving While Intoxicated (DWI) charges throughout Missouri and Metro East Illinois, including those arrested at sobriety checkpoints. Understanding what happens during these stops can help protect an individual’s rights.

Are DUI Checkpoints Legal in Missouri?

Yes, DUI checkpoints are legal in Missouri. The U.S. Supreme Court upheld the constitutionality of sobriety checkpoints in Michigan Department of State Police v. Sitz (1990). The Court applied a balancing test and determined that the state’s interest in preventing drunk driving outweighed the brief intrusion on individual liberty.

Missouri courts have also upheld the legality of these checkpoints, provided law enforcement follows specific constitutional requirements during their operation.

However, there’s an important development. The Missouri legislature defunded the state’s checkpoint program in 2017, allocating only $1 per year for checkpoint operations, according to reports from the Missouri House Appropriations Committee. This means that while checkpoints remain legal, they are now rare in Missouri because most law enforcement agencies lack the funding to operate them.

Today, Missouri police departments more commonly use “saturation patrols” with increased officer presence targeting impaired drivers through traditional traffic stops.

What Happens at a DUI Checkpoint in Missouri

When approaching a DUI checkpoint in Missouri, here’s what typically occurs:

Initial Stop

Officers stop vehicles according to a predetermined, neutral formula. This might mean stopping every vehicle, or every third or fifth vehicle. The U.S. Department of Justice requires this neutral selection process to prevent arbitrary stops or profiling.

Law enforcement must supervise checkpoints by senior officers and use clearly marked vehicles and uniforms. Warning signs and signal lights should alert drivers that a checkpoint is ahead.

Brief Interaction

An officer approaches the vehicle and typically asks for the driver’s license, vehicle registration, and proof of insurance. According to the Supreme Court’s decision in Michigan v. Sitz, this initial interaction usually lasts approximately 25 seconds for most drivers.

During this brief stop, the officer observes the driver for signs of impairment, including the smell of alcohol, slurred speech, bloodshot eyes, or difficulty producing documents.

Further Investigation

If the officer observes signs of intoxication, the driver may be directed to a secondary screening area. At this point, the officer may:

• Ask questions about where the person has been and whether they have been drinking
• Request that the driver perform field sobriety tests
• Administer a preliminary breath test (PBT)

According to Missouri Revised Statutes § 577.020, Missouri’s implied consent law applies after arrest, not during the initial roadside screening.

Arrest Decision

If the officer develops probable cause to believe the driver is operating a vehicle while intoxicated, that person will be arrested and transported for chemical testing under Missouri’s implied consent law.

Do Drivers Have to Stop at DUI Checkpoints?

Yes, a driver is legally required to stop at a DUI checkpoint in Missouri once they’ve entered the checkpoint lane. Failing to stop when directed by law enforcement can result in additional charges.

Can Someone Avoid a Checkpoint?

A driver can legally turn away from a checkpoint before entering it, provided no traffic laws are violated in the process. However, officers are typically stationed specifically to watch for drivers who attempt to avoid checkpoints.

If someone makes an illegal U-turn, fails to signal, or commits any traffic violation while avoiding the checkpoint, officers will pull that vehicle over. At that point, the officer has probable cause for a traffic stop independent of the checkpoint.

Rights at a DUI Checkpoint

Understanding rights at a Missouri DUI checkpoint is crucial:

Right to Remain Silent

A driver must provide their license, registration, and proof of insurance. Beyond that, there is no requirement to answer questions about where someone has been or whether they have been drinking.

According to the Fifth Amendment of the U.S. Constitution, every person has the right to remain silent to avoid self-incrimination.

Field Sobriety Tests

Field sobriety tests are voluntary in Missouri. These roadside tests are not mandatory, and declining to perform them carries no administrative penalty like license suspension.

However, if someone refuses field sobriety tests and the officer still has probable cause to make an arrest based on other observations, that person can still be arrested for DWI.

Preliminary Breath Tests

The handheld preliminary breath test (PBT) administered at the roadside is also voluntary. This is different from the official breath test conducted after arrest at the police station.

Missouri’s Implied Consent Law

Once someone is arrested for DWI at a checkpoint, Missouri’s implied consent law applies. Under RSMo § 577.020, anyone who operates a vehicle in Missouri is deemed to have given consent to chemical testing of breath, blood, saliva, or urine if arrested on probable cause for DWI.

Chemical Testing After Arrest

After arrest, the officer will request that the person submit to a chemical test. The officer must inform the arrested individual:

• That they are under arrest for DWI
• The type of test being requested
• That refusing the test will result in a one-year license revocation
• That evidence of refusal can be used against them in court

According to RSMo § 577.041, if someone requests to contact an attorney, they have 20 minutes to attempt to do so.

Consequences of Refusal

If someone refuses chemical testing after a DWI arrest in Missouri, the Missouri Department of Revenue will revoke that person’s driver’s license for one year. This is an administrative penalty separate from any criminal charges.

The officer will confiscate the physical license and issue a 15-day temporary permit. To challenge this revocation, an administrative hearing must be requested within 15 days of the arrest.

What Officers Look for at Checkpoints

Law enforcement officers conducting DUI checkpoints are trained to identify signs of impairment quickly. They observe:

Physical Indicators

• Bloodshot or watery eyes
• Flushed face
• Slurred or thick speech
• Fumbling with documents
• Difficulty with motor skills

Odor

The smell of alcohol on a person’s breath or in the vehicle is one of the most common observations noted in police reports from checkpoint arrests.

Behavior

• Confusion or disorientation
• Inappropriate responses to questions
• Unusual nervousness beyond normal checkpoint anxiety
• Inability to follow simple instructions

According to research published by the National Highway Traffic Safety Administration, officers use these observations to determine whether further investigation is warranted.

Constitutional Requirements for Legal Checkpoints

For a DUI checkpoint to be constitutional under Missouri law, it must meet specific criteria established by the courts:

Supervisory Decision

The decision to establish the checkpoint must be made by supervisory law enforcement personnel, not officers in the field.

Public Notice

Some form of advance public notification is required. While the exact location doesn’t need to be disclosed, the public must be informed that checkpoints will occur in the area.

Neutral Selection Process

Vehicles must be stopped according to a predetermined, neutral formula. Officers cannot select vehicles based on the driver’s appearance, vehicle type, or other subjective factors.

Minimal Intrusion

The checkpoint must be designed to minimize the intrusion on motorists. Most stops should last less than one minute for drivers who show no signs of impairment.

Safety Measures

Checkpoints must have proper lighting, warning signs, and marked police vehicles to ensure the safety of both motorists and officers.

Why Checkpoint DWI Cases Are Defensible

Many people assume that being arrested at a DUI checkpoint means there is no defense. That assumption is incorrect. These cases can be challenged in several ways:

Checkpoint Legality

If law enforcement failed to follow constitutional requirements, the checkpoint itself may be deemed illegal. This could result in the suppression of all evidence obtained during the stop.

Lack of Probable Cause

Officers must still develop probable cause to arrest someone for DWI. If the arrest was based on insufficient evidence or improper field sobriety test administration, the charges may be challenged.

Testing Issues

Chemical breath tests can be challenged based on machine calibration, maintenance records, officer training, and proper testing procedures.

Violation of Rights

If officers violated constitutional rights during the checkpoint stop, evidence obtained after that violation may be suppressed.

What to Do If Arrested at a Checkpoint

If someone is arrested for DWI at a checkpoint in Missouri:

Contact an Attorney Immediately

The sooner a criminal defense attorney is involved, the better. We can begin investigating the case, preserving evidence, and protecting rights from the start.

Request an Administrative Hearing

There are only 15 days to request an administrative hearing to challenge a license suspension. Missing this deadline means the license will be automatically suspended or revoked.

Preserve Evidence

If someone believes the checkpoint was conducted improperly, noting the time, location, and any details about how it was operated could be crucial to the defense.

Don’t Discuss the Case

Cases should not be discussed with anyone except an attorney. Statements made can be used in court.

Take Action Now

If someone has been arrested at a DUI checkpoint in Missouri, time is critical. There are only 15 days to challenge an administrative license suspension, and the sooner we can begin working on the criminal defense, the better the chances of achieving a favorable outcome.

At Rose Legal Services, we offer consultations for individuals facing DWI charges. We will review the circumstances of the checkpoint stop, explain rights and options, and discuss how we can help defend the case.

We are passionate about helping good people get a second chance. Being arrested is not the same as being convicted, and we will work to achieve the best possible outcome in each case.

Don’t let a checkpoint DWI arrest dictate the future. Contact Rose Legal Services today to schedule a consultation with our experienced DWI defense team.

Your defense starts with a conversation.