Florida Drunk Driving Defense Attorney Reveals the Truth About Faulty Breath Test Evidence

When someone is arrested in Florida for DUI, the first piece of evidence the State clings to is the breathalyzer reading. I’ve seen it time and time again—officers and prosecutors try to treat that number as the final word. But I’ve been defending DUI clients in Florida for years, and I can tell you, that number is not the whole story. It can be wrong. It can be challenged. And in many cases, it can be thrown out.

Let me walk you through how I, as a Florida Drunk Driving Defense Attorney, tear into breathalyzer results and fight to protect your future.

WHAT FLORIDA LAW SAYS ABOUT DUI AND BREATH TESTS

Under Florida Statutes §316.193, it is unlawful to drive or be in actual physical control of a vehicle while:

  • Impaired by alcohol or controlled substances, or

  • Having a blood-alcohol level (BAL) of 0.08 or more grams of alcohol per 100 milliliters of blood or 210 liters of breath.

The statute reads:

“A person is guilty of the offense of driving under the influence… if the person is driving or in actual physical control of a vehicle within this state and:
(a) The person is under the influence of alcoholic beverages… to the extent that the person’s normal faculties are impaired;
(b) The person has a blood-alcohol level of 0.08 or more…”

But just because a machine spits out a number above .08 doesn’t mean the case is closed. That number is only as reliable as the procedures used and the conditions at the time of testing.

COMMON BREATHALYZER ISSUES THAT CAN LEAD TO UNRELIABLE RESULTS

As a Florida Drunk Driving Defense Attorney, I start by asking this: was the breathalyzer machine functioning properly, and was it operated according to the strict standards required by Florida law?

Here are just a few of the flaws I look for in DUI breath test cases:

1. MACHINE MAINTENANCE FAILURES
Florida requires regular maintenance and calibration of breath testing devices, such as the Intoxilyzer 8000. If the agency failed to follow proper maintenance schedules under Florida Administrative Code Rule 11D-8, I will request records, examine logs, and challenge the admissibility of the results.

2. OPERATOR ERROR
Only trained and certified individuals can operate breath test machines. If the officer administering your test wasn't certified or skipped required steps—like the 20-minute observation period—I will expose that in court.

3. PHYSIOLOGICAL CONDITIONS
Medical conditions such as GERD (acid reflux), diabetes, or a high body temperature can skew results. Even mouthwash or dental work can trap alcohol and produce false readings. I’ve had cases where clients with acid reflux blew high numbers, but medical records showed the true cause.

4. INTERFERING SUBSTANCES
Some common chemicals, both in the environment and in the human body, can cause false positives. Paint fumes, cleaning agents, and even certain diets (like keto) can impact breath test results.

5. IMPROPER OBSERVATION PERIOD
Florida law mandates a 20-minute observation period before a breath test to ensure nothing was placed in the mouth. If the officer left the room or got distracted, we can argue that the sample may have been contaminated.

WHY PRIVATE DUI DEFENSE COUNSEL MAKES A DIFFERENCE

If you think a public defender or walking into court alone will get your breath test dismissed, you’re setting yourself up for disappointment. These cases are technical. The smallest procedural misstep can be grounds for suppression—but only if it’s discovered and presented properly.

As a private attorney, I bring in my own forensic breath test consultants, subpoena every single calibration and maintenance record, and cross-examine officers in evidentiary hearings. I treat the machine like it’s on trial, because many times, that’s what makes or breaks your case.

REAL CASE EXAMPLE: BREATH TEST SUPPRESSED, DUI DISMISSED

One of my clients—a nurse—was stopped after rolling through a stop sign. The officer claimed she smelled alcohol and had her perform field sobriety tests. She complied and then submitted to a breath test that showed 0.11.

Here’s what I uncovered:

  • The Intoxilyzer 8000 hadn’t been properly calibrated in over a month.

  • The officer administering the test wasn’t certified for breath test operations in the state of Florida.

  • No 20-minute observation period occurred—surveillance footage showed the officer walking away multiple times.

I filed a motion to suppress the breath test based on these violations. The judge granted it. Without the breath result, the prosecutor couldn’t prove impairment beyond a reasonable doubt. The DUI was dismissed, and her nursing license remained safe.

FLORIDA STATUTES THAT SUPPORT YOUR DEFENSE

Beyond §316.193, other statutes and administrative rules come into play when challenging breath tests:

  • Florida Administrative Code Rule 11D-8.002–8.012 – Covers breath test instruments, inspections, and operational protocols.

  • §316.1932 – Covers implied consent and allows breath test refusal under penalties.

  • §90.702, Florida Evidence Code – Permits expert testimony challenging the reliability of breath test results.

  • §316.1934(5) – States that breath test results must be from “an approved instrument operated in accordance with the methods approved by the Department of Law Enforcement.”

Every one of these laws gives me tools to punch holes in the prosecution’s case.

DEFENSES WE MAY USE IN YOUR CASE

Every DUI case is unique, but here are defenses I commonly apply to challenge breath test results:

  • The test result was obtained through an unlawful arrest.

  • Improper calibration or maintenance of the breath device.

  • The officer failed to conduct a valid observation period.

  • My client had a medical condition that caused a false reading.

  • Chain of custody issues with breath test logs or software records.

  • Violation of Florida’s Implied Consent Law procedures.

  • The breath sample was not taken within a reasonable time after driving.

  • My client’s right to counsel was obstructed before submitting to testing.

Each defense becomes a tool. And I know how to use every single one.

WHY YOU CAN’T AFFORD TO RISK A DUI CONVICTION

A DUI on your record doesn’t go away easily. Even a first offense can lead to:

  • Jail time

  • License suspension

  • Fines and court costs

  • Probation

  • Vehicle impoundment

  • Ignition interlock device

  • Employment and insurance problems

And if you’re a nurse, teacher, commercial driver, or military service member, your professional license or career could be on the line.

You need a private attorney with the time and resources to scrutinize every step of the DUI investigation. I don’t just look at the breath test number. I look at everything before, during, and after that test. That’s what wins cases.

WHY MUSCA LAW?

I’m part of a defense team that covers the entire state of Florida with over three decades of courtroom experience. We have handled thousands of DUI cases and aggressively challenged faulty breath test results from Key West to Pensacola.

Our network of offices, legal resources, and scientific consultants allows us to work quickly and thoroughly. Whether you were arrested in Orlando, Miami, Tampa, Jacksonville, or anywhere in between, we are prepared to fight for you.

FLORIDA DRUNK DRIVING DEFENSE FREQUENTLY ASKED QUESTIONS

Can I be convicted of DUI even if my breath test was under .08?
Yes. Florida allows prosecutors to charge DUI based on observed impairment. But in those cases, the breath test actually helps the defense. I’ve won many cases where my client tested under .08 and we used that to argue they weren’t impaired.

What happens if I refused the breath test?
Refusing a breath test carries an automatic license suspension of one year for the first refusal and 18 months for a second, along with potential misdemeanor charges for repeat refusals. However, refusal also means the State doesn’t have breath test evidence. I often use this as a defense advantage.

Can I get the breath test thrown out?
Yes, under certain conditions. If the machine wasn’t calibrated, the operator wasn’t certified, or legal protocols were violated, I can file a motion to suppress. If the court grants it, the result is excluded from evidence.

What is the Intoxilyzer 8000 and why does it matter?
It’s the breath test machine Florida uses. But it’s also a machine that has had its share of controversy and technical problems. I’ve used software glitches, faulty sensors, and noncompliance with calibration logs to undermine its reliability in court.

Does the officer have to watch me for 20 minutes before testing?
Yes. Florida requires a 20-minute observation period to ensure you don’t burp, vomit, or place anything in your mouth. If the officer fails to do this—or can’t prove they did—I can argue the test is invalid.

What if I have asthma or another breathing problem?
Medical conditions can make it impossible to give a proper breath sample or may cause false results. I’ve had success using medical records and physician testimony to challenge DUI breath test cases based on this.

Will a DUI conviction stay on my record forever?
Unless the charge is dismissed or reduced to a lesser offense, a DUI conviction will stay on your criminal record permanently. Florida does not allow DUI convictions to be sealed or expunged. That’s why beating the case is so important.

Can I challenge a breath test even if I failed badly?
Yes. Even a .15 or higher reading can be challenged. I’ve had cases where the client blew over .20 and still walked free because we proved the test was unreliable. Never assume the number means you’re guilty.

Do I have to go to court if I hire a private lawyer?
In many misdemeanor DUI cases, I can appear on your behalf. For felony DUI or trial settings, your presence may be required. But I handle all filings, hearings, and motions. You won’t face this alone.

Why hire a private Florida Drunk Driving Defense Attorney?
Because you need someone with the time and resources to review every piece of evidence. Public defenders are overworked. The prosecutor won’t do you any favors. A private attorney focuses on your case, your defenses, and your freedom.

SPEAK WITH OUR FLORIDA DRUNK DRIVING DEFENSE ATTORNEY TODAY

Musca Law, P.A. has a team of experienced criminal defense attorneys dedicated to defending people charged with a criminal or traffic offense. We are available 24/7/365 at 1-888-484-5057 for your FREE consultation. We have 35 office locations throughout all of the state of Florida and serve all counties in Florida including Jacksonville, Miami, Tampa, Orlando, St. Petersburg, Hialeah, Port St. Lucie, Cape Coral, Tallahassee, Fort Lauderdale, and the Florida Panhandle.

If your future is riding on a breath test result, don’t face the State alone. Let’s fight it—together.