DUI Investigations Phase I | Vehicle in Motion

DUI Attorney | DUI Investigation

DUI Investigations

Fort Lauderdale DUI Attorney | Miami DUI Attorney

Phase I DUI Investigations | Vehicle in Motion

Police officer’s are trained to follow the guidelines set forth by the National Transportation and Safety Administration(NHTSA) when conducting a DUI investigation. The guidelines set forth 3 stages to every DUI arrest. The officers are trained to identify “cues” of impairment in each stage of the investigation. The cues are used to develop probable cause to support a traffic stop and an arrest.

Phase I, Vehicle In Motion Phase I of a DUI investigation is broken down into three subparts.  It consists of a) the observation of the vehicle while it is being driven; b) the decision to make a traffic stop; and c) observations made during the traffic stop. The initial observation of the vehicle begins when the officer, for whatever reason, notices the vehicle. The officer may have witnessed the driver commit a traffic infraction or just thought “Hey! Nice car!” The reason why the officer notices the vehicle is not relevant.

Once the officer notices the vehicle, the officer is trained to look for 24 specific cues that NHTSA has determined to have a statistically significant correlation to impairment. The correlation of the cues range from .35 to .90. Accordingly, one indication of impairment is not going to be probable cause for a DUI stop. The probability that an individual is impaired increases with the number of cues exhibited by the driver.  Typically, officers are looking for two or more cues.  It is important to realize that any traffic infraction can be used as a basis to stop a vehicle even if the infraction is not a specifically listed cue.

NHTSA has divided the driving behaviors into four categories:

  • Problems in maintaining proper lane position | Statistical Correlation to Impairment .50- .75

Weaving Weaving across lane lines Straddling a lane line Swerving Turning with a wide radius Drifting Almost striking a vehicle or other object

  • Speed and braking problems | Statistical Correlation to Impairment .45 – .70

Stopping problems (too far, too short, or too jerky) Accelerating or decelerating for no apparent reason Varying speed Slow speed (10+ mph under limit)

  • Vigilance problems |  Statistical Correlation to Impairment .55 – .65

Driving in opposing lanes or wrong way on one way Slow response to traffic signals Slow or failure to respond to officer’s signals Stopping in lane for no apparent reason Driving without headlights at night Failure to signal or signal inconsistent with action

  • Judgment problems. Statistical Correlation to Impairment .35 – .95

Following too closely Improper or unsafe lane change Illegal or improper turn Driving on other than designated roadway Stopping inappropriately in response to officer Inappropriate or unusual behavior (throwing objects, arguing, etc.) Appearing to be impaired

It should be noted that many times an individual is stopped for excessive speed and nothing more. Excessive speed is NOT an indication of impairment. However, varying speed and slow speed are indications.  Special attention should be paid to the police report to see which cues listed by the officer are statistically correlated.  Quite often, there are no statistically significant cues.  While it will not usually not win a motion to suppress based on the stop, if the officer also witnessed a traffic violation, it is nice to be able to highlight to the jury that there were no indications of impairment based on the driving pattern.

In trial, or in a hearing, the prosecution tends to point to 2 or 3 cues of impairment to establish that a person was too impaired to drive. A good defense strategy is to focus on the 21 or 22 things that the defendant did correctly. A cross examination focusing on what the defendant did right is an extremely effective strategy when there is a “double refusal” meaning that the defendant did not take the roadside sobriety exercises and the defendant did not take a breath, blood or urine test.

When selecting a DUI attorney, ask the attorney about his or her additional training and education with regard to the NHTSA Standardized Sobriety Tests and the 3 Phases of a DUI arrest.  The NHTSA Student Manual is available to attorneys and all serious DUI attorneys should have one.

For additional information, please contact

The Law Offices of Michael A. Dye, PA, 1 E Broward Blvd #700, Fort Lauderdale, FL 33301 (954)990-0525 or
The Law Offices of Michael A. Dye, PA, 2 S Biscayne Blvd, Miami, FL 33131 (305)459-3286

Next: DUI Investigations Phase II

Roadside Sobriety Exercises | Standardized Field Sobriety Tests

DUI Attorney

Police officer incorrectly administering the SFST’s.

DUI Attorney Miami | Criminal Lawyer Miami

Prior to being arrested for a DUI, and sometimes afterwards, the police often ask a defendant to submit to a series of exercises in order to determine the individual’s sobriety.  These exercises are known as the Standardized Field Sobriety Tests or SFST’s for short. The SFST’s is a series of 3 tests that the National Highway Transportation and Safety Administration has determined can be used to identify impairment in an individual.  The officer demonstrates and then observes the defendant perform the exercises.  The officer is trained to identify certain indicators of impairment that can be used to establish probable cause for an arrest or to simply pile on additional evidence of impairment.

The exercises must be administered and evaluated in a standardized fashion in order to ensure an accurate result.  The tests were developed by NHTSA in conjunction with the Southern California Research institute.  There are only 3 SFST’s that are statistically correlated to impairment.  Those tests are the Horizontal Gaze Nystagmus, the Walk-And-Turn and the One-Leg Stand.   These 3 tests are to be administered the same way every single time and evaluated through the use of strict criteria limiting an officer’s discretion as to what is a “pass” or what is a “fail.”

The unfortunate reality is that the standardized administration and evaluation of the SFST’s is largely ignored by police departments and individual police officers.  The exercises are frequently administered and evaluated incorrectly leading the officer to form an opinion that can not be validated by any of the studies or research.  Additionally, officers that are not properly trained often use improvised exercises that have been found to have no correlation to impairment.  The most common of these tests are the “finger to nose” test, any test involving the alphabet and a wide variety of different counting exercises using your fingers.  Do not be mistaken, those tests are not approved to detect impairment.  Many DUI attorneys are not familiar with the concepts involved with the SFST’s.

When consulting with a criminal lawyer concerning your DUI case, you should ask the lawyer:

1)  Are you familiar with the SFST’s?

2)  What additional training have you received in the administration and interpretation of the SFST’s?

3)  Do you own a copy of the NHTSA SFST Manual?

4)  Approximately how many trials have you had where you cross examined the arresting officer concerning the NHTSA criteria?

DUI Attorney, Michael Dye received additional training in the administration and interpretation of the SFST’s from Doug Scott, a pioneer in the field of the Drug Recognition Expert Program, who is recognized as an expert in the administration and interpretation of the SFST’s.  Mr. Dye has the most current version of the NHTSA SFST Student Manual and actively utilizes it as reference and impeachment material in both depositions and trials.  Mr. Dye has cross examined the arresting officer regarding the SFST’s in over 20 trials and numerous depositions.

For additional information, please contact

The Law Offices of Michael A. Dye, PA, 1 E Broward Blvd #700, Fort Lauderdale, FL 33301 (954)990-0525 or
The Law Offices of Michael A. Dye, PA, 2 S Biscayne Blvd, Miami, FL 33131 (305)459-3286

Police Must Have Warrant to Search Cell Phone Data


On June 25, 2014, The Supreme Court of The United States issued its opinion in the case of Riley v. California.  The court combined the cases of Riley v. California and United States v. Wurie as the two cases presented identical issues.

Both cases involved the police searching an individual’s cell phone after the individual had been lawfully placed under arrest.  The police did not just physically search the cell phones, but rather searched the data inside the cell phones in furtherance of their investigation and in order to find potentially incriminating information.  In the Riley matter, the search of the cell phone revealed that the defendant was a member of a street gang and also involved in a shooting.  Riley was convicted of the shooting and received a sentencing enhancement for being a member of a street gang based off of the information police obtained from his cell phone.  In the Wurie matter, the police accessed the call log on the defendant’s telephone and traced certain numbers with suspicious activity.  As a result, Wurie was charged and convicted of several drug and firearms offenses.

The Fourth Amendment of the United States Constitution protects an individuals right to be secure in their person and property.  It prohibits searches without a warrant signed by a neutral and detached magistrate specifically stating the items to be found and where the items are to be found.  There are limited exceptions to the “warrant requirement.”  A warrantless search, and the information derived therefrom, is only admissible if the warrantless search falls within a specific exception to the warrant requirement.

One specific exception to the warrant requirement is “search incident to lawful arrest.”  However, the search is limited to the area within the arrestee’s immediate control.  The search is justified for the purposes of officer safety and to prevent the destruction of evidence.  When asked to extend the search incident to lawful arrest to cellular phones, the Supreme Court ruled that a search of the digital information on the phone does not serve the government’s two purposes for warrantless searches.  The search of the digital information on the phone is not justified as a means to protect officer safety.  While it could possibly be argued that there is a potential for the destruction of evidence, that is balanced against the individuals privacy interest which, when it comes to the search of the data on a phone, is significantly greater than a brief physical search.  Nevertheless, the Supreme Court found that the data stored on cell phones does not present a threat to officer safety or a potential for the destruction of evidence.

While the digital data stored by a cell phone does not present any imminent threat to an arresting officer’s safety, the officer is still free to examine the physical features of the cell phone in order to ensure that it cannot be used as a weapon.  While the destruction of evidence via “remote wiping” is certainly a possibility, the Supreme Court does not rule out the ability of the police to disable a telephone in order to prevent remote wiping and secure the scene.  The court also provides for the police to search an individual’s telephone without a warrant under the exigent circumstances doctrine.

For additional information, please contact

The Law Offices of Michael A. Dye, PA, 1 E Broward Blvd #700, Fort Lauderdale, FL 33301 (954)990-0525 or
The Law Offices of Michael A. Dye, PA, 2 S Biscayne Blvd, Miami, FL 33131 (305)459-3286