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What Evidence Is Needed for a DUI Conviction?

Serving Families Throughout Jacksonville
DUI conviction

How to Fight It in the State of Florida

A DUI charge (driving under the influence) is serious business. You face the possibility of fines, jail time and a conviction that will stain your record for a long time. Buying car insurance will become more difficult and expensive, if not outright impossible.

In other words, it’s worth your time and effort to fight this charge in court. We know that it can seem impossible to dispute the case the state is making against you. We can tell you that there is hope. The state of Florida has clear standards on the evidence needed for a DUI conviction and plenty of ways your attorney can contest what the state puts forward against you.

The evidence needed for a DUI conviction is that you must have been in physical control of the vehicle and under the influence of alcohol or some other chemical substance. This influence needs to have been high enough to either impair your normal faculties or produce a blood or breath alcohol level of at least 0.08.

The 0.08 alcohol level, as measured by either a breathalyzer or a blood test, is a hard-and-fast standard. It means you have .08 grams of alcohol per 100 milliliters of blood or 210 liters of breath. The standard of “impairing normal faculties” is defined by Florida law as “the ability to see, hear, walk, talk, judge distances, drive an automobile, make judgments, act in emergencies, and in general, to normally perform the many mental and physical acts of our daily lives.”

That’s the standard of proof for a DUI in the state of Florida. It’s the prosecution’s responsibility to meet it. It’s your defense lawyer’s job to challenge their evidence.

3 Sources of DUI Evidence

The prosecution will build its case off of what’s available through field sobriety tests, chemical tests and the police report.

Field Sobriety Test–This is what may have happened after the officer pulled you over. It will be available on video recorded by the officer’s dashboard camera. That video must be made available to your defense lawyer as a part of the discovery process.

The field sobriety test is requested by the officer and can include methods that seek to monitor your eyes and your balance.

Chemical Tests–The chemical test might have been a breathalyzer, done in conjunction with field sobriety tests. It can also include blood tests or a urine sample that are done after the officer brings you to the station.

Police Reports–This is the arresting officer’s eyewitness account of what happened.

These evidentiary sources will have varying degrees of authority in a court of law. There are ways to effectively challenge all of them.

Challenging the Evidence

The first step is to see if there was any reason for you to be pulled over to begin with. An officer must have reasonable suspicion to turn on their flashing red lights and pull up behind you. Reasonable suspicion can be driving erratically. It might also be breaking a traffic law. Maybe you rolled through a stop sign or perhaps your car was starting to straddle the centerline. That would be reasonable suspicion to make a stop.

After pulling you over, the officer must have probable cause to believe you might meet the legal definition of intoxication. If you slur your speech, that’s a huge red flag. Smelling alcohol on your breath would also qualify.

The state’s burden of proof on reasonable suspicion and probable cause are not high. But a part of your lawyer’s due diligence involves making sure they exist. If not, your case can be thrown out.

Challenging the Field Sobriety Test

An officer might have asked you to extend your arm and then bring your finger all the way back to touch your nose. The purpose would be to test your hand-eye coordination. But there are other ways a person might fail this test other than being intoxicated.

The same goes for any other field test you might be put through, whether it’s walking and turning or balancing on one leg. Some people have medical conditions that impact these areas. There are natural differences in the motor skills that people have.

Weather conditions can also impact how you handle the field sobriety test. A person being asked to step out in the pouring rain or onto an uneven surface is less likely to perform well than someone pulled over in perfect conditions on a newly paved highway.

Furthermore, whether you “failed” this test was in the judgment of the arresting officer. An officer gifted with fine motor skills might be less understanding of why someone without these skills would fail the Hand-to-Eye test.

The good news is that the presence of video means the court does not have to simply take the officer’s word for it. If you and your attorney determine that the video will help exonerate you, it can be presented at trial.

It’s possible the video footage might not have come out well. For the most part, that’s a positive development for the defendant. Obviously, if you believe the officer’s interpretation of your field sobriety test performance was wrong, you might prefer to have clear and convincing evidence to the contrary. But a failure to produce reliable video footage can be even more damaging to the prosecution’s obligation to prove your guilt beyond a reasonable doubt.

One final note about the video–it keeps going after you enter the patrol car. This is a good time to exercise your right to remain silent. It’s also a good idea not to fall asleep. We know if you were arrested at one in the morning, you may well just be exhausted. But a court might also interpret this as a sign of intoxication.

Challenging the Chemical Test

It can seem ironclad in the state’s favor. After all, you blew an .08 on the breathalyzer, so you’re guilty, right? Not so fast.

Breathalyzers are not infallible instruments. They need to be calibrated properly. The arresting officer must also have been trained in its usage. Failure to care for the device or to ensure personnel knew how to use it can be used to get the results dismissed in court.

Furthermore, any number of dietary and medical issues can create a misleading result on a breathalyzer test. The simple act of belching can cause your reading to be higher than it otherwise might have.

Common medical conditions—ranging from diabetes to acid reflux to heart problems—can all create misleadingly high breathalyzer results. So can the medication you might take for asthma.

There are foods that can also trigger the breathalyzer. Cakes and bread are a common example. The mouthwash you use, along with oral gels, can have a similar effect.

So, let’s consider this scenario. You went to your mother’s 80th birthday party. You had a piece of cake and a glass of champagne. On the way home, on a mostly empty street, you went through a yellow light way too late, right at the point it turned red. An officer pulls you over and picks up a whiff of champagne.

The officer is fine so far. They have reasonable suspicion and probable cause. Not much of either one, but enough to have pulled you over and put you through the tests. They pull out the breathalyzer and you blow a 0.09. You’re arrested and taken to jail.

You know that a single glass of champagne didn’t make your alcohol level that high. But you feel like the breathalyzer is the smoking gun.

Left unchallenged it can be. That’s why your defense lawyer should be asking you everything about the evening up to the point of your arrest. The piece of cake may have triggered the high result. Maybe your lawyer also finds out you deal with reflux. Now we’ve got two different factors that could have influenced a breathalyzer result that had you barely over the legal limit as it was.

You might not know about these potentially mitigating factors when you’re arrested. It’s your attorney’s responsibility to uncover the truth.

Challenging the Police Report

We won’t say challenging a police report is easy. But the subjective nature of this evidence does allow several pathways to question it. All human beings have biases and police officers are no different. Their bias has to be uncovered and then examined for how it may have impacted everything from the decision to pull you over, to asking for the field test, to performing the chemical test and, finally, how they presented it all in the report.

You also have a constitutional right to confront your accuser in court. If two police officers were present at your arrest, but only one of them appears to testify, your attorney can challenge more than just the report. They can challenge the entire legitimacy of the trial.

An experienced defense attorney is extremely important when fighting a DUI charge. Everything from your record to your reputation to your freedom is on the line. You need someone who knows how to ask the questions–of both you and of the police–that will strengthen your case.

The Law Offices of Jason K.S. Porter, P.A has a team of legal talent that knows how to fight hard on behalf of those who are accused of crimes. Call us today at (904) 701-0591 or contact us online to tell us what happened and see how we can help.
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