DUI Law

DUI Traffic Stop: FAQ

Key Takeaways

  • During a traffic stop, the police can look for signs and evidence of impairment.
  • Police officers use breathalyzers and field sobriety tests to get evidence for probable cause to make an arrest.
  • Drivers can remain silent and ask for their attorney after a DUI traffic stop.

Getting pulled over for driving under the influence (DUI) is a stressful experience. Knowing what happens during a traffic stop can help you prepare if police ever stop you. Below are answers to some frequently asked questions (FAQs) about DUI traffic stops.

DUI laws are different in every state. Contact an experienced criminal defense attorney for legal advice after a DUI arrest.

When Do Police Officers Stop Impaired Drivers?

Law enforcement officers are trained to look for signs of impaired driving. The National Highway Traffic Safety Administration (NHTSA) has even put out a guide on the visual detection of DWI motorists. This includes 24 cues predicting blood alcohol concentrations (BACs) of 0.08% or higher. Signs of impaired driving can include:

  • Weaving 
  • Swerving 
  • Almost striking another motor vehicle or object 
  • Slow speed
  • Driving in opposing lanes
  • Driving without headlights at night 
  • Improper or unsafe lane change 

When officers see signs of possible impairment, they can stop the driver to investigate further.

What Signs of Impairment Do Police Look For During a DUI Traffic Stop?

During a suspected DUI stop, the police will continue to look for signs of impairment from the driver. Signs the driver is under the influence of alcohol include:

  • The smell of alcohol from the driver
  • Open containers in the vehicle
  • Smell of drugs or visual drug paraphernalia
  • Slurred speech
  • Bloodshot eyes

When talking to the driver, the police may look for contradictions or inconsistencies in the driver’s story. The police can also ask the driver if they’ve had anything to drink.

What Do You Have to Say to the Police?

A traffic stop generally starts with the police officer asking for your driver’s license, proof of insurance, and vehicle registration. The officer may then ask whether you’ve been drinking or where you were coming from. You don’t have to answer any questions if you think it will hurt your DUI case.

Under the Fifth Amendment to the U.S. Constitution, you have the right to remain silent and not to say anything that might incriminate you. If you say you’ve been drinking, the police may have enough probable cause to make an arrest. If you say you were not drinking, but the officer smells alcohol, they will probably arrest you.

How High Can My Blood Alcohol Content Level Be Before It Is Illegal To Drive?

For most drivers, the legal limit for BAC is 0.08 percent. In Utah, the limit is 0.05%. However, for those under 21, many states have a zero-tolerance policy for underage drinking and driving. Any amount of alcohol detected by a breathalyzer can result in an underage DUI.

Commercial drivers operating a commercial vehicle have a lower legal limit. For motorists with a commercial driver’s license, a higher than 0.04% BAC can mean they lose their license for one year. A second commercial DUI can result in a lifetime commercial driving ban.

How Will Officers Test Whether or Not I Am Drunk?

Officers have multiple means of determining whether or not you are under the influence. This includes dangerous driving and signs of alcohol during the traffic stop. As part of the traffic stop, the police may also have you perform field sobriety tests. Field sobriety tests are roadside tests that determine possible impairment. There are three standard tests, which include:

  • Horizontal Gaze Nystagmus Test (HGN): This test involves the officer monitoring your eyes for involuntary jerking movements.
  • Walk and Turn Test: This test typically involves walking in a straight line, heel-to-toe, turning around, and walking back.
  • One-Leg Stand Test: This test often involves standing on one foot while counting to 30.

In most jurisdictions, these tests are optional. There are no penalties for refusing to perform a field sobriety test. However, whether you do the tests or not, the police can still arrest you if they have probable cause that you are impaired.

Do You Have to Take a Roadside Breathalyzer Test?

A roadside breathalyzer test estimates your BAC. Also known as preliminary alcohol screening devices, these can give the officer probable cause to arrest you for drunk driving. However, these test results are not evidentiary. Handheld breathalyzers are not used as evidence to prove you are driving while impaired. In many states, these tests are not mandatory.

Am I Required To Take a Chemical Test?

After a DUI arrest, you have to submit to a chemical breath or blood test. States have implied consent laws that require chemical tests. When you get a driver’s license, you give implied consent to chemical BAC tests after a drunk driving arrest. This means that refusing to take one can result in stiff penalties, including a driver’s license suspension.

Some states also have criminal penalties for refusal. Penalties for refusing a blood or breath test can include fines and mandatory jail time. Even if you refuse to take a BAC test, it may not protect you from a DUI conviction. The prosecutor can use other evidence at trial, like the results of field sobriety testing or witness testimony. Police can also get a warrant to force you to undergo a blood test.

Can I Speak With a Lawyer Before Taking a Test?

Your rights before a chemical test can depend on state law. Some states allow drivers to consult a lawyer when deciding whether or not to take a chemical test. However, you likely won’t have long to talk with a lawyer and should not attempt to stall for time. Other states do not allow you to speak with a lawyer before testing.

Can the Police Ask Questions Before Reading My Rights?

People are familiar with Miranda rights from TV shows and movies. However, the police don’t always have to read your rights before making an arrest, especially if they are not conducting an interrogation at that moment. Miranda warnings relate to interrogation and police questioning. In many DUI cases, the police don’t need to rely on your statements or a confession. Evidence of impairment will come from chemical tests, police reports, and field sobriety tests.

What if an Officer Doesn’t Follow Protocol?

Officers have strict rules and procedures when they pull you over for a DUI. They must have reasonable suspicion and probable cause to arrest you. Without probable cause, your DUI defense attorney can challenge the evidence in your case.

The police must also follow specific procedures when administering field sobriety and breath tests. If they don’t give the right instructions or follow the monitoring rules, the evidence can be compromised. Talk to your DUI defense lawyer if you think the officer didn’t follow the law during a traffic stop.

Should I Get a DUI Lawyer?

Each DUI case is different. Consulting a DUI lawyer can help you understand your legal options. A DUI lawyer can negotiate with the prosecutor to reduce your charges or get a plea deal. If it is your first offense, you may be eligible for a diversion program to drop the charges. Your lawyer can also defend you in court. If you need legal representation after a DUI traffic stop, talk to a local DUI attorney.

Was this helpful?

At LawInfo, we know legal issues can be stressful and confusing. We are committed to providing you with reliable legal information in a way that is easy to understand. Our pages are written by legal writers and reviewed by legal experts. We strive to present information in a neutral and unbiased way, so that you can make informed decisions based on your legal circumstances.