Although many driving under the influence (“DUI”) cases (also called “driving while intoxicated” or “DWI”) are resolved before trial through plea bargaining, DUI defendants generally have a constitutional right to a jury trial.
Most defendants on trial for DUI have never been in court. The formal trial process might be intimidating, especially because different courts can have slightly different procedures. This article provides an overview of the typical procedures a defendant might expect in a standard DUI trial.
Jury Selection for a DUI Trial
Trial procedures vary by jurisdiction, but typically a jury trial begins with jury selection.
DUI Jury Trial Voir Dire
Jury selection is known as “voir dire” (which literally means “to speak the truth”). During voir dire, the prosecutor and defense attorney question a group of potential jurors (the “jury pool”). Based on their answers, the prosecutor and defense attorney can dismiss jurors using what are called “peremptory challenges” and “challenges for cause.”
Peremptory Challenges to Potential Jurors
Peremptory challenges can generally be used to dismiss a juror for any reason. However, peremptory challenges can’t be used in a way that discriminates on the basis of race, ethnicity, or gender.
Each side has a limited number of peremptory challenges, which varies by jurisdiction and whether the case is a misdemeanor or felony. For example, some jurisdictions allow each side three peremptory challenges in misdemeanor cases and six peremptory challenges in felony cases.
Challenges for Cause to Potential Jurors
A challenge for cause is the dismissal of a juror based on the juror’s bias, prejudice, or any other reasons that would prevent the juror from serving on the jury. Each side is allowed an unlimited number of challenges for cause. But the court ultimately decides whether the challenge is sufficient to dismiss a juror.
Number of Jurors in DUI Trials
The goal of voir dire is to select a group of jurors that are impartial and agree to follow the law when deciding the case. In a felony case, there are normally 12 jurors, whereas in a misdemeanor case (most DUI cases involve only misdemeanor charges), the jury may be comprised of as few as six jurors.
Opening Statements for DUI Trials
The actual trial begins with opening statements by the prosecutor and then the defense attorney. An opening statement is generally a preview of the evidence that each party intends to present.
No evidence is presented during opening statements, and the attorneys aren’t supposed to make legal arguments to the jury. Rather, the attorneys are supposed to use their opening statements to outline for the jury what they believe the evidence will show. In other words, the parties explain, from their perspective, what the facts of the case are.
What the Prosecution Needs to Prove for a DUI Conviction
In a criminal case, a defendant is innocent until proven guilty. The prosecutor must prove the defendant committed the crime of DUI “beyond a reasonable doubt.” Generally, a reasonable doubt means a real possibility that a defendant is not guilty. If the jury has any reasonable doubt as to the defendant’s guilt, they must return a not guilty verdict.
Because the government has the burden of proof, the prosecution presents its case first. In a DUI trial, the state’s case might include, for example, testimony from the arresting officer, lay witnesses who saw the defendant driving, and expert witnesses such as a lab technician who analyzed a blood or urine sample. The prosecutor may also present blood alcohol concentration (BAC) test results, photographs, and/or videos of the stop, field sobriety tests, and arrest. (Read about what the prosecution must prove for a DUI conviction.)
The prosecution questions its witnesses through direct examination, with the goal of eliciting information to strengthen the state’s case. After direct examination, the defendant’s attorney will have an opportunity to cross examine any witnesses that testify for the state. A defendant’s cross examination typically involves attempting to cast doubt on the witness’s testimony or to bring out information favorable to the defense.
How Defendants Fight DUI Charges at Trial
After the state presents its case, the defense can present its own case. However, a criminal defendant doesn’t have to present any evidence or testify. It’s up to the state to prove the defendant’s guilt. So, in many cases, the defense strategy is to attack the state’s evidence rather than present evidence of their own.
Types of Evidence a DUI Defendant Can Use
In a DUI case, the defense might present the testimony of lay witnesses and expert witnesses in an effort to establish that the defendant wasn’t impaired at the time of driving. The defendant may also choose to present videos or photographs, if favorable to the defense. In the same manner as the state, the defense questions its witnesses through direct examination and the prosecutor can cross-examine the defense’s witnesses.
Common DUI Defenses Used in Court
For anyone charged with DUI, it’s important to know whether the circumstances present any good defenses. Most DUI defenses focus on either the legalities of the arrest procedures or weaknesses in the prosecution’s evidence.
Here are some of the most common methods defense attorneys use to fight DUI charges in court.
- Attacking illegal searches and seizures. The 4thAmendment to the U.S. Constitution (and similar provisions of state constitutions) prohibits unreasonable searches and seizures by police. This rule applies to traffic stops and certain aspects of DUI investigations—like drawing blood without a warrant. Evidence that’s acquired by police as the result of an illegal search or seizure generally can’t be used in court against the defendant. This defense usually is raised before trial through a pretrial motion.
- Confronting the prosecution’s evidence that the defendant was driving. In DUI and all other criminal trials, the prosecution must prove the charges beyond a reasonable doubt. The prosecutor generally most show that the defendant was driving, operating, or in “actual physical control” of a motor vehicle. The defendant can use evidence—like witness testimony or dashboard camera videos—that police didn’t catch the defendant in the act of driving. In states that require only “actual physical control,” the defendant can provide evidence that they weren’t in a position to readily start up the car and drive away.
- Disputing FSTs as evidence of intoxication. Prosecutors generally must prove that a DUI defendant was “under the influence” of drugs or alcohol or had a blood alcohol concentration (BAC) of .08% or more (.05% in Utah). The prosecution often uses field sobriety tests (FST) to prove intoxication. A driver might explain that poor FST performance was due to a physical disability, being extremely tired, or that the police conducted the test incorrectly.
- Attacking chemical tests as evidence of intoxication. When it comes to chemical test results (blood and breath tests being most common), defenses often attack the reliability of the equipment or process used to measure the defendant’s alcohol level. For example, an improperly maintained breathalyzer might not give accurate results. And, if blood tests aren’t handled properly, they can ferment and subsequently contain an artificially high level of alcohol.
- Using the rising-blood-alcohol defense. There’s also a defense, called the “rising-blood-alcohol defense” that’s based on the science of how the body metabolizes alcohol—the general idea is that the defendant’s BAC might have risen above the legal limit after driving but prior to taking the chemical test.
Closing Arguments in DUI Trials
After the parties “rest” (finish presenting evidence), the prosecutor and defense attorney give closing arguments. Closing arguments are the last opportunity for the attorneys to address the jury before deliberations.
Generally, the prosecutor attempts to convince the jury that the evidence requires a guilty verdict. Conversely, the defense’s closing argument typically tries to establish that the state hasn’t met its burden of proof and the jury must find the defendant not guilty. After closing arguments, the prosecutor can make a final rebuttal argument.
Jury Instructions, Deliberations, and Verdict in DUI Trials
Prior to jury deliberations, the judge gives the jury instructions, which are the legal standards the jury must use to decide the case. Then, the jury privately deliberates, attempting to agree on whether the defendant is guilty or not guilty of DUI. Most states require a unanimous jury decision in criminal cases.
Once the jury reaches a verdict, the foreman informs the judge and the verdict is announced in open court. If the defendant is found not guilty of DUI, the case is over. (However, depending on the jurisdiction, administrative penalties that were imposed by the Department of Motor Vehicles, such as a driver’s license suspension, might remain in effect.)
If the jury returns a guilty verdict, the judge will sentence the defendant in accordance with the DUI laws of the particular state. If the jury is unable to reach a unanimous verdict, the judge declares a mistrial, and the case will either be dismissed or tried again in front of a new jury.
Talk to an Experienced DUI Lawyer
If you're facing a DUI trial, it's always a good idea to have a qualified DUI attorney at your side. After being arrested for driving under the influence, you should get in contact with an experienced DUI lawyer as soon as possible. A DUI lawyer can help you decide on the best course of action, whether that's going to trial or plea bargaining.