The number on the printout feels final. A breath test result above 0.08 in a Florida DUI case carries what the law calls a presumption of accuracy, and most people assume that presumption is unshakeable. After 29 years handling criminal cases on both sides of the courtroom, I can tell you it isn’t. The device that produced that number has a maintenance history, an inspection record, and a chain of regulatory requirements behind it. When any part of that chain breaks, the result loses its legal footing.
Florida doesn’t use generic breathalyzers. The state’s primary evidentiary breath test instrument is the CMI, Inc. Intoxilyzer 8000, governed by Florida Administrative Code Chapter 11D-8 and administered by the FDLE Alcohol Testing Program. That specificity matters because it means there are concrete rules, concrete records, and concrete consequences when those rules aren’t followed.
Why the Intoxilyzer 8000 Isn’t Infallible
The Intoxilyzer 8000 uses infrared spectroscopy, a process that identifies compounds in a breath sample by measuring how they absorb infrared light, to estimate blood alcohol concentration (BAC). The technology is sophisticated, but it’s also sensitive. The sensors that measure absorption drift over time. The heating elements that regulate sample chamber temperature can malfunction, skewing results upward. Software errors, though less common, have produced falsely elevated readings in documented cases.
Reliability depends entirely on consistent, properly documented maintenance. Florida Statute 316.193 ties criminal liability to the BAC number, so the integrity of the device that generates it isn’t a technicality. It’s the foundation of the prosecution’s case.
Florida’s Maintenance Rules & Where Agencies Fall Short
Florida Administrative Code Rule 11D-8.006 requires agency inspectors to inspect evidentiary breath test instruments at least once each calendar month. The results of every inspection must be documented on FDLE/ATP Form 40 and electronically uploaded to the FDLE Alcohol Testing Program within five business days. A device that hasn’t been inspected on schedule, or whose inspection records weren’t uploaded in time, has a compliance gap that can be challenged in court.
The rules around repairs are equally strict. Only the manufacturer or an approved repair facility may service the Intoxilyzer 8000. Any repair performed outside that authorization is considered unauthorized under Florida rules. Beyond those two requirements, agencies sometimes keep devices in active service after a failed inspection rather than pulling them from rotation, or a power outage destroys inspection data entirely. These aren’t hypotheticals. They’re documented patterns that show up in real case records.
What Courts Have Done When Maintenance Fails
Florida courts have already drawn the line on what unauthorized maintenance does to a breath test result. In the Kilburn case, a court excluded breath test results entirely after FDLE inspectors replaced the breath tube themselves, a repair they weren’t authorized to perform. That single maintenance misstep stripped the device of its presumption of accuracy, and the result was thrown out.
Equipment failure isn’t unique to Florida. Massachusetts identified more than 27,000 DUI convictions affected by improperly maintained breathalyzers covering arrests from 2011 through 2019. In New Jersey, more than 20,000 people were convicted between 2008 and 2016 based on results from devices that a state police sergeant had failed to calibrate correctly. These aren’t edge cases. They’re evidence that breath testing equipment fails at a systemic scale when oversight slips.
Once a documented maintenance failure strips the presumption of accuracy, the prosecution can’t simply point to the printed BAC number. It must affirmatively prove that the specific device was functioning correctly at the specific time of the test, a much harder burden that changes the entire shape of the case.
What I Actually Examine in the Records
Challenging a breath test result means pulling the records tied to the specific device used in a specific arrest and looking for documented gaps. Through formal discovery, I obtain the device’s serial-number maintenance history, every agency inspection report filed on FDLE/ATP Form 40, operator certification records confirming the officer who administered the test was properly trained, and any repair logs the agency holds.
Several patterns signal a problem worth pursuing:
- Missed monthly inspections that leave a gap in the required inspection calendar
- Late uploads where Form 40 results weren’t transmitted to FDLE within the five-business-day window
- Unauthorized repairs performed by agency personnel rather than the manufacturer or an approved facility
- Devices returned to service without a proper FDLE clearance inspection following a repair or failed inspection
When those gaps exist, the path forward is a motion to suppress, a formal pre-trial request asking the court to exclude the BAC reading from evidence. A successful motion doesn’t automatically end the case, but it forces the prosecution to build its argument around officer observations and field sobriety test results alone, which is a substantially weaker position than a number on a printout.
How This Defense Plays Out in Pinellas County
DUI cases arising from St. Petersburg arrests are heard at the Pinellas County Justice Center in Clearwater, following the consolidation of criminal traffic cases from South County Traffic Court in January 2019. Maintenance record challenges are litigated there as pre-trial motions to suppress before the case ever reaches a jury.
My background as a former prosecutor shapes how I approach these motions. I know how the state builds a BAC-centered case, and I know which gaps in a maintenance record prosecutors are least prepared to address at a suppression hearing. When the maintenance chain is clean, that shapes one strategy. When it isn’t, the records become the defense.
Every DUI case involves a specific device with a specific serial number and a specific inspection history. That record is where the defense investigation begins, not the printed number it produced. If you’re facing a DUI charge in St. Petersburg based on a breath test result, contact Joseph Montrone, Jr. at (727) 617-6095 to talk through what the records actually show.