Mistakes Made by DUI Police in Greater Phoenix

by Aaron M. Black • June 04, 2021

Mistakes Made by DUI Police in PhoenixAnyone can make a mistake, even greater Phoenix region law officers and prosecutors. Mistakes made in procedures, traffic stops, arrests, faults in testing equipment, and inadequate storage of evidence impact DUI cases involving alcohol, prescriptions, or illicit drugs.

Although authorities are obligated to protect the civil and property rights of the population, there are a few bad actors among them who complicate the dynamic further by intentionally making mistakes to help their own agendas.

Mistakes made by law officers lead to wrongful DUI convictions, exonerations, or dismissals of the charges.

Mistakes making traffic stops

The first step in a traffic stop requires that the officer have reasonable suspicion of a crime or traffic violation.  Only once an officer has probable cause a crime occurred can he/she arrest. So, if you are stopped for a traffic violation and an officer detects the smell of alcohol, he/she can try to develop probable cause via odor of alcohol, sway, slurred speech, driving behavior, admissions, field sobriety tests, or any other indicators of impairment.
Reasonable suspicion: Reasonable suspicion is defined as a justifiable suspicion that the particular individual to be detained is involved in criminal activity.  The test is an objective one.  Only when there are specific, articulable facts that present a substantial possibility that a specific individual has committed or is committing a criminal offense may a police officer detain that individual.  The law requires that police have a founded suspicion that the person they are stopping is involved in criminal activity.  As a general matter, the decision to stop an automobile is reasonable where the police have reasonable suspicion to believe that a traffic violation has occurred.  It is a violation of the Fourth Amendment to stop a vehicle based on facts that neither constitutes a violation of the law nor reasonable grounds to suspect the driver has committed an offense.

The Fourth Amendment to the United States Constitution provides “The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated.” Its protection against unreasonable seizures extends to brief investigatory stops of persons or vehicles that fall short of traditional arrest. A police officer may make a limited investigatory stop in the absence of probable cause if the officer has an articulable, reasonable suspicion, based on the totality of the circumstances, that the suspect is involved in criminal activity. This can be a traffic violation  or possible impairment.

Probable Cause: An arrest must be based on probable cause.  In Arizona probable cause is defined as "such a state of facts as would lead a man of ordinary caution or prudence to believe and consciously entertain a strong suspicion of guilt." An arrest is unlawful if not based on probable cause.  Probable cause exists only when reasonably trustworthy information of the facts and circumstances within knowledge of the arresting officer at the time of arrest were sufficient to warrant a man of reasonable caution to believe that a criminal offense had been committed by the person to be arrested.  Suspicion alone is not enough.  Probable cause is more than mere suspicion.  Facts that would cause the officer to investigate the matter further differ from facts that support a finding of probable cause. An arrest without probable cause is illegal. 

Errors administering field sobriety tests

An officer, in conducting the DUI traffic stop, will want to administer a field sobriety test consisting of a series of movements. The walk and turn, standing on one leg, touching finger to nose and the nystagmus test to check irregularities in eye movement. These tests are designed and validated by the National Highway Traffic Safety Administration (NHTSA).

Officers do make mistakes when administering these tests, rendering them invalid and not admissible into evidence. The physical condition of the suspect can negatively affect the test results. For example, failing to stand on one leg to check balance could actually be the result of an issue in the inner ear.

The officer cannot require you to take a field sobriety test. In fact, requesting the suspect to take these tests is an invitation to convict yourself. In declining to take the test, the prosecution can argue that you knew you were at or above the legal limit.

The breathalyzer test will show if you have consumed alcohol and if so how much beyond the baseline DUI of 0.08 percent of blood-alcohol concentration (BAC). The officer was required to be trained in this procedure and certified in how to use the breathalyzer. But if the training was not adequately mastered, the test results can be invalidated. It might be that the breathalyzer itself was out of calibration and produced inaccurate results.

Mistakes making a DUI arrest

During the traffic stop the officer will ask questions. How much have you had to drink tonight? What drugs have you taken? Where are you coming from? Such questions are invitations to convict yourself.

Anything said will be used by the prosecution to win a conviction. The best response to questioning is to tell the officer you want to talk to an attorney and the questioning should stop.

At the point of the actual arrest, you have the right to not answer incriminating inquiries. The Fifth Amendment protects you from self-incrimination.

The officer now must recite the Miranda rights, which gets its name from a U.S. Supreme Court ruling in 1966 stemming from an Arizona DUI arrest.
In reciting the Miranda rights, the officer tells the driver he or she has the right to remain silent and to have an attorney present during questioning and if you cannot afford an attorney one will be appointed to represent you. The officer will ask if you understand these rights.

If the officer fails to recite the Miranda Rights at the point of arrest, the case will be dismissed on grounds that your constitutional rights were violated.

Mistakes in police reports

The police report is the basis for charging a DUI. The officer describes the probable cause for making the traffic stop, what the driver says and does during the stop, and why the officer believes the driver was under the influence. The prosecutor uses the police report, among other evidence, to build a case.

Sometimes the arresting officer does not keep the notes taken during the investigation after the police report is submitted to the prosecutor. Then in court months later, without the notes, the officer must rely on distant memory of the stop, investigation, and arrest. This mistake allows the defense, under cross examination, the possibility to establish a reasonable doubt in the minds of jurors leading to an acquittal.

It can happen that an officer’s police report contains fabrications.

Contaminated evidence

The prosecution must protect the samples of physical evidence during storage throughout the case. Mistakes in police protocols and procedures, handling, and preserving blood, breath and urine evidence while in storage contaminates these samples. If the evidence is improperly labeled, doubt of their accuracy can be raised.

Evidence tampering

Police or a third party technician can tamper with evidence by destroying, fabricating, removing or concealing physical evidence intending to effect the result of a trial. Tampering is both unethical and illegal in state and federal cases. Using as evidence any document or record that is known to be false is another form of tampering.

If the physical evidence was accidently destroyed the prosecution cannot use it.

In your defense

It is crucial to be represented by an experienced local DUI defense attorney, such as myself, at the earliest possible time after a DUI arrest. I will conduct my own investigation into the charges, the handling of physical evidence, and capitalize on any mistake law enforcement has committed and hold them accountable. A DUI lawyer working in Phoenix has an advantage over attorneys from out of state since they will be unfamiliar with the Valley of the Sun.

My goal is always to earn a dismissal of the charges or at the very least to have the DUI charge reduced to a lesser offense. During your case, you will always be talking directly to me so you will know everything first hand. You will not be relegated to an assistant.

Launch your Phoenix DUI defense by calling 480-729-1683, which is available 24/7, and I will respond promptly unless I am in court on in trial. Or use my online contact form on my website.

I defend DUI cases in Phoenix federal, state, municipal, and justice courts in and adjacent to Maricopa County.

About Criminal Defense Attorney Aaron M. Black
The National Trial Lawyers Association rated me among the top 100 trial lawyers in the country. The National Association of Distinguished Counsel placed me in the top one percent of the finest lawyers in the nation. And for the 8th consecutive year, I have been named a 2021 DUI Super Lawyer in Phoenix by the Southwest Super Lawyers magazine.


About the Author

Aaron Black Phoenix DUI LawyerAaron Black is the founder and sole attorney of the Law Office of Aaron Black. Located in Phoenix, Arizona, his DUI and criminal defense law firm provides legal services to people who have received felony or misdemeanor charges from the state.

Aaron has developed a strong interest in defending people who have been arrested and received criminal charges for driving under the influence. With his professionalism and knowledge of Arizona DUI and criminal law, he has acted as a check and balance on the police, prosecution and courts and has protected a great number of his clients from excessive and unfair sentencing.

Along with DUI defense, Aaron handles a range of other criminal defense matters, including aggravated assault, burglary, domestic violence, drug possession, drug trafficking, fraud defense, insurance fraud, sex crimes, and white-collar crime cases.

After graduating college in 2003 from the University of Arizona, Aaron decided to pursue a law degree. He followed a family long tradition and went to the University of South Dakota School of Law where he pursued his goal of becoming a criminal defense lawyer.

After passing the Arizona and South Dakota bar exams, Aaron joined the Maricopa County Office of the Public Defender where he defended hundreds of people charged with serious criminal offenses. His work as a public defender helped him sharpen his litigation skills and gave him a unique insight into the Arizona criminal justice system.

Over the course of his 15-year legal career, Aaron has spent a considerable amount of time in both Arizona justice, municipal, state and federal courts. He has argued over 50 jury trials, tried over 100 bench trials and has become one of the highest-rated criminal and DUI defense attorneys in Phoenix and the surrounding areas. He has received a 10/10 rating from the legal directory Avvo because of his legal background and successful case record. Since 2014, he has received the Super Lawyer rating for his work as a Phoenix DUI Attorney and criminal defense attorney.

You can review Aaron’s Attorney Bio page for more information about his background, education and experience as a Phoenix DUI and criminal defense attorney.
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