The DUI Bust: What Happened?

All of the following elements are likely to play a role in your DUI case.

Now that you know more or less what a DUI charge is and the range of possible penalties, let's turn to what likely happened in your DUI case. After we get to the point where you have obtained the police report in your arraignment, we'll help you analyze your case in light of the probable case the prosecution will bring to the table.

The Stop

If your case was at all typical, you were driving your car when you were stopped by a pair of law enforcement officers for either obvious signs of impairment, such as swerving in your lane or other erratic driving, or some violation of the law (for anything from a broken taillight to speeding—it doesn't make any difference). As long as the officers had probable cause to believe you were either violating any law or were under the influence of alcohol or a drug, they have a right to pull you over.

If the police truly had no probable cause to pull you over, later in your case you can bring a motion to suppress, which can result in the entire case being thrown out.

The Officer's Observations

Once you were pulled over, you were asked to produce your license and registration. If you seriously fumbled your attempts to get your documents, or there was any evidence of alcohol or drug use—typically smells emanating from your breath or, in the case of marijuana, the smoke—you were asked to step out of the car. From this point on, every move you made was carefully observed for possible evidence of impairment and noted for later use against you. These observations will pop up in the police report, which you will see for the first time in your arraignment (described below).

The Inquisition

Once out of the car or even while you were still in it, you were asked if you had had anything to drink recently (or similar questions if marijuana or another drug was implicated). If you were like most people who had been drinking, you might have said, "just a beer or two with dinner" or some other underestimation about how much you drank. Oops. Law enforcement personnel engaged in traffic regulation have heard those lines so many times that they're almost probable cause on their own for them to go further. Even worse, if for any reason your case goes to trial and you truthfully testify that you had four or five beers instead of the original two, the prosecution will hammer you for having lied to the officer. While this may be the most human thing to do under the circumstances, the jury may not see it that way.

When Your Car May Be Searched

If the police suspect drug use or have reason to suspect that drugs might be in your car, they have a right to search the car without getting a warrant. The search may include the trunk, the glove box, and even closed containers (although the police will sometimes get a warrant for them if it's convenient). The police will typically ask if you will consent to search, and if you say yes you can't challenge the search later. If you make it clear that you don't consent and they proceed to search without a warrant, you sometimes can get the results of the search suppressed on the ground the officers lacked probable cause. (See below.)

Roadside Tests

Once the officers decided they had a basis to go further, they likely ran you through a few roadside tests, called field sobriety tests, and they also may have informed you that you could take a preliminary breath test.

The Preliminary Alcohol Screening Test (PAS)

The preliminary breath test is often called the preliminary alcohol screening test or PAS, although the name varies from state to state. When the officers offered you this test, they may have informed you that taking the test might result in your release if the result was low enough and drugs weren't also indicated. If the officers were doing their job right, they also explained that the PAS test is not the same as the mandatory test that you could still be required to take under your state's implied consent laws. (See "Mandatory Chemical Tests and Implied Consent," below).

The PAS test result may have surprised you. Rates of absorption and elimination of alcohol from the body are tricky to compute; they vary considerably according to a number of variables. For more about this, read "All About Alcohol," at the end of this chapter.

PAS tests, by definition, have been made possible because of the development of portable breath testing machines that would produce an immediate readout. Formerly, the police wouldn't have any idea what your breath showed your BAC to be until they took the sample back to the police station, sent it to the state laboratory, and waited (sometimes weeks) for the result. Now, the machines used for the PAS are said to be as reliable as the machine used for the mandatory test (assuming you chose the breath test). In fact, at least one of the machines available for general use boasts equal reliability for PAS and the mandatory test under the implied consent law (the Dräger Alcotest 7410).

Even though the new machines are reliable, they must be calibrated regularly. If they aren't, their results may not be admissible in court. The issue of calibration is discussed in more detail below.

Which machines were used in your case, and whether they were properly calibrated, will likely be a function for your state's (and community's) budget. For valuable information about these machines and some of the possible problems to look for, see the latest edition of Drunk Driving Defense, by Lawrence E. Taylor (Aspen) or California Drunk Driving Defense, by Lawrence E. Taylor (Thomson West). You also can get some good information about these machines on a number of lawyer websites, not least of which is one maintained by Professor Taylor at

The Field Sobriety Tests

In addition to the PAS you were likely given the following field sobriety tests:

  • Horizontal gaze nystagmus, where the officer asked you to move your eyes back and forth while looking at a flashlight or stick while he or she measured the angle at which certain involuntary twitches occurred in your eyes.
  • Standing on one foot while counting. In this test, the officer was looking for swaying while balancing, using arms to balance, hopping, and putting a foot down.
  • Walking ten steps heel to toe and then turning around in a certain way and walking back, counting all the while. In this test, there are eight cues of possible impairment:
    • can't balance during instructions
    • starts too soon
    • stops while walking
    • doesn't touch heel to toe
    • steps off the line
    • uses arms to balance
    • loses balance on turn or turn incorrectly, and
    • takes the wrong number of steps.

More on the Horizontal Gaze Nystagmus Test

In the horizontal gaze nystagmus test, there are three clues for each eye. Essentially the clues are whether:

  • your eyes move smoothly or jerk noticeably
  • your eyes jerk when you have moved them to the side as far as possible, and
  • your eye starts to jerk before it has moved through a 45-degree angle.

Virtually every police officer who conducts this test believes that the subject has flunked, but cross-examination by defense attorneys usually defeats this evidence because of the conditions of the test and the difficulty in accurately measuring the very small eye movements and angles that measure success or failure of the test.

You don't flunk or pass these tests. Rather the police use them as general indicators of possible impairment and will testify that you were impaired if you fail to correctly perform just a couple of steps on even one of the tests.

These tests come from the National Highway Traffic Safety Administration (NHSA). While each state has its own practices and can use its own tests, most states use these national tests because doing so adds credibility to the prosecutor's argument that the tests are good indicators of impairment.

If you go on to a DUI trial, you can and should learn more about what these tests do and don't mean. For example, the fact that you miss a few steps in a test will only indicate a 68% chance that you were impaired. This point would be brought out in cross-examination of the officer. For now, however, it's enough to know that your behavior on these tests is not conclusive of your guilt.

These three tests all come with required ways (from the NHTSA) for administering and interpreting them (level ground, actual or imaginary line for the walk and turn test, hands at side, count to ten by thousands, etc.), and departure from these standards would provide a way to rebut any negative implications arising from your performance.

If you are interested in knowing more about or challenging these or other field sobriety tests in a trial, obtain a copy of the latest edition of the previously mentioned Drunk Driving Defense, by Lawrence E. Taylor (Aspen). If you are in California, use the most recent edition of California Drunk Driving Defense, by Lawrence E. Taylor (Thomson West) or California Drunk Driving Law, by Ed Kuwatch, Paul Burglin, and Barry Simons (James Publishing).

You may have also been given other field sobriety tests, such as closing your eyes and estimating when 30 seconds has passed, putting both index fingers on your nose, counting backward from 100 by sevens, and having the officer take your pulse (to test for methamphetamine or marijuana). The National Highway Traffic Safety Administration disfavors these other tests because they have been shown over the years to not be very reliable in proving a person under the influence. Still, they may be used in your state and will have to be taken into account in case you go trial.

The chart "Indicators Consistent With Drug Categories," below, shows which of these additional field sobriety tests indicates the possible presence of drugs.

The Police Report

The first thing people want to see after they've been arrested for DUI is the report setting out the police version of events. In most states this won't be available to you until your arraignment, described below. Since the police report (and maybe some additional lab reports) will pretty much describe the entire case against you, getting hold of this document is crucial to deciding whether to fight the charges. Later we explain how to get, read, and understand the police report. For now, we want you to be aware that for you the police report is the holy grail of criminal defense.

Mandatory Chemical Tests and Implied Consent

After the PAS and the field sobriety tests, you were told that you were required to take a blood, breath, or urine test under your state's "implied consent" laws.

Every state has implied consent laws that require drivers to submit to a chemical test when law enforcement officers have probable cause to believe the drivers have been driving under the influence of alcohol or drugs. Drivers can usually choose between a blood or breath test for blood alcohol content and a blood or urine test if drugs are suspected. Some states still use urine tests in alcohol cases, although this is being phased out because of its lack of reliability.

By applying for and receiving a driver's license, you are presumed to have agreed to take one of these tests if asked to under the appropriate circumstances—thus the term "implied consent." To see the implied consent laws for your state (and consequences of refusing a test) visit www

If you refused to take the test, you will be subject to a number of penalties, which vary from state to state. If you agreed to take a test, it most likely confirmed the PAS result and the officer's perception that you were driving under the influence or driving with more than .08 blood alcohol content. To learn more about how alcohol interacts with your system, how long it remains, and the approximate amounts you can drink at a particular body weight without going over the .08 limit, see "All About Alcohol," later in this chapter.

Refusing to Take the Mandatory Test

Attorneys are often asked about when it's best to take the test and when to refuse it. As a general rule, you will seldom benefit from refusing the required test unless you have a recent prior DUI conviction. If you refuse to take any of the tests offered you will likely face a license suspension of the same length or even longer than would be the case if you took the test and were convicted of DUI. In fact, Alaska provides jail time for refusal to take the test, and a few other states provide for increased jail time if you are convicted of DUI after refusing the test. For your state's penalties for test refusals, see

Another reason to take the test is that the fact of your refusal can be used in a trial to argue that you knew you were over the limit—and this could result in a longer suspension than if you had taken the test and were found guilty at trial. And the final kicker? In a few states the police can forcibly draw blood if you refuse to submit to a test voluntarily, and some states require an ignition interlock for people who refuse the test.

On the other hand, you may come out ahead by refusing if you have recent priors (within seven to ten years) that will affect the charge in the current case, and if you have enough self-awareness to know you would flunk the test anyway.

Arrest, Detention, and Release

If the arresting officers concluded that you were probably driving under the influence of alcohol or drugs (or both), you may have been deprived of your license on the spot and provided with a temporary license that allowed you to drive until the court or your state's motor vehicle department decided to suspend your license for a specified period of time based on the facts of your case. You were also likely cuffed, put in the squad car, and taken to the local jail (unless you were tested at the jail in the first place), where you were booked, cited for the offenses, and either released when you appeared to no longer be under the influence or detained at the jail until you were bailed out or released by the judge on your own recognizance the next day. If you were arrested on a Friday and not bailed out, you might have spent the weekend in jail. If you were in jail, the good news is that you'll get credit for "time served" and most likely won't have to return even if you plead (or are found) guilty. Of course if you fight the case and win, you won't be compensated for your unpleasant experience.

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