A Primer on the Subtle Art of Litigating DUI Motions
There are several kinds of motions that a DUI lawyer may bring before a case gets anywhere near trial. This article gives a general overview of the types of motions, when they are generally brought, and what they accomplish.
Procedural DUI Motions: Procedural motions cover a wide range of mechanical functions, including the requesting and disclosing of evidence from both the prosecution and the defense, motions to compel witness interviews or depositions, motions to continue, motions for change of venue and change of judge, motions regarding identification lineups or photo show-ups, motions to have blood or urine reexamined by an independent laboratory, and many other issues.
Substantive DUI Motions: Substantive motions are, as the title implies, motions of legal substance. They include issues such as Miranda violations, involuntariness of statements, motions to dismiss for lack of probable cause and reasonable suspicion, motions regarding the admissibility of evidence obtained without a search warrant, motions regarding certain evidentiary issues, the constitutionality of police actions and the DUI statutes and regulations themselves.
Motions In Limine: In addition to procedural and substantive motions, a DUI attorney may preemptive bring motions regarding the flow of evidence in trial before the trial starts. These are referred to as “motions in limine.”

The time limits and deadlines for the various types of motions vary from state to state, so please check with your DUI defense lawyer to see what motions may be right in your case, and when they will need to be filed.
Make sure you cooperate with your lawyer by providing him or her all the information necessary to assess the merits of any substantive or procedural DUI motion the lawyer may be considering.
Let’s look at a couple of hypotheticals to illustrate the skill and thought that must go into any decision to bring a motion in a DUI case:
Scenario 1, the missing witness: There is a civilian witness mentioned in the police report. He is the only person who can place you behind the wheel of your vehicle. Without his testimony, the judge will have to throw your case out. Your DWI lawyer had attempted to contact him several times, and has not gotten any response. If your jurisdiction allows your lawyer to compel a deposition for an uncooperative or unresponsive witness, the question will be “should your DUI attorney file the motion.”
Pros: If you file it, you will know the witnesses availability. If the witness responds, you will know what he will say if called to testify against you. If he doesn’t respond, the judge might preclude his testimony, which means that you win. Sounds pretty good, but…
Cons: What if the witness doesn’t want to cooperate, and if left alone would not cooperate with either the state or the defense? If your DUI lawyer compels him to court, he is probably going to show up, and he’s probably not going to be happy about it. In this scenario, if your lawyer had not kicked that hornet’s nest, your case would have been dismissed.
This is a tough call, and only your DUI lawyer can make the ultimate decision. It often times helps for the lawyer to get a feel for where the prosecutor stands on the matter. Sometimes, enough information can be extracted from the prosecutor to make a good decision.
Scenario 2, the missing information in the police report: Perhaps there is a gap in the police report. Let’s say there is some missing time that can’t be accounted for based on any of the involved officers’ accounts of the event. For this example, say they can’t establish the time of driving becaue the police are called in after an accident. They need the time of driving to be able to prove that you had a 0.080 or greater alcohol concentration within two hours of driving.
You have two options:
- Bring a motion to suppress the breath test because they can’t show time of driving; or
- Sit on the issue and wait for trial.
The pros and cons of bringing this issue as a substantive motion:
Pros: You could win. The potential of losing could bring the prosecutor to the table with a good plea bargain.
Cons: You tip the prosecutor off to the weakness in their case while they still have time to round up the evidence to fill the gap. Perhaps it is as easy as pulling up a dispatch report, or as difficult as tracking down a witness to the accident and getting a sworn statement. Either way, if you let well enough alone perhaps the issue survives to the day of trial where your DUI lawyer can use it to get the charge thrown out.
There are literally hundreds of other scenarios that could come up in your DUI case. Only your DUI lawyer can advise you on the pros and cons of any particular action in your individual case.



