Every breath result is the output of a computer program. The Intoxilyzer 8000 runs on internal software, the source code, that tells it how to read your sample, when to accept it, and how to turn light into a number. That code is written and held by the manufacturer, and for years defense lawyers have fought to see it.
The source code matters because the machine’s most important decisions happen inside it, out of view. The fight over access has been real, and the Florida results have mostly favored the State. Knowing where that fight stands is part of an honest breath defense.
What the Source Code Is
Source code is the set of instructions a computer follows. In the Intoxilyzer 8000, it governs the slope check, the interferent logic, the averaging of samples, the tolerances, and what the machine prints. If there is an error or a buried assumption in that logic, it affects every test the machine runs. The hardware and the maintenance records are visible. The code is not.
Breath goes in, sealed software processes it, and a number comes out that the State treats as conclusive. The decisions in between are made by code that the defense has rarely been allowed to examine.
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A breath reading at or above 0.08 also starts the 10-day license clock.
A breath result over the limit triggers an administrative suspension on top of the criminal case. You have 10 days from the arrest to demand a formal review hearing with the DHSMV in Clearwater, which protects your license and can secure a 42-day permit. We file that request the same day you hire us. Call or text (727) 761-4318.
The Access Fight in Florida
Defense attorneys have moved to compel the source code so an expert could examine it. Florida courts have generally said no, holding that a defendant has to make a specific showing of why the code is needed before a court will order it produced. See State v. Bastos, 985 So. 2d 37 (Fla. 3d DCA 2008). The manufacturer, CMI, is based in Kentucky, and Florida courts have also held that the code could not be reached through the usual out-of-state subpoena process. See CMI, Inc. v. Landrum, 64 So. 3d 693 (Fla. 2d DCA 2010). The honest picture is that direct access has been hard to win.
Why It Still Matters
Even without the code itself, its existence shapes the defense. The same court that denied access acknowledged that the machine can produce false positives, because it reads only part of the infrared spectrum and cannot single out ethanol from every other compound. We use the machine’s outputs, the printout, the error codes, and the inspection records, to show how the software behaved in your case, and we keep the closed-source problem in front of the jury as a reason the number deserves scrutiny.
Why This Matters in Your Case
A number produced by sealed software, treated as proof beyond a reasonable doubt, deserves hard questions. We press the access issue where the facts support it, and we build the defense around what the machine’s own records reveal. This connects to how the Intoxilyzer 8000 works and the interferents the software is supposed to catch.
The breath goes in and a number comes out, but the code that decides the result has never been fully opened for independent inspection. The reliability of the output depends on software no one outside the maker has audited in full.
The Black Box Problem
Every result the machine produces is the output of software that decides how to read the sample, when to accept it, how to apply the slope and interference checks, and how to turn absorption into a number. That software is treated as a trade secret. When the code is not open to independent review, no one outside the manufacturer can confirm that it does what it claims, that its checks work as described, or that it is free of errors. A jury is asked to trust a number from a process that has not been verified by anyone who does not sell the device.
Why Independent Review Matters
Software has bugs. A defense has a legitimate interest in examining the code that generated the evidence against a person, the same way it can examine a human analyst’s work. Where courts have allowed a look, reviewers have raised questions about how these instruments handle their own checks and edge cases. The point is not that the software is necessarily wrong, but that its correctness has been asserted rather than demonstrated, and a criminal case should not rest on an unexamined assertion.
What We Request
We pursue access to the relevant software and documentation where the case warrants it, and we pair that with the instrument’s calibration records and the printout data, so the machine’s behavior can be examined from the outside in. When the State will not or cannot open the box, that itself is part of the argument about how much weight the number deserves.
A breath machine is asked to carry enormous weight in a courtroom while the code that runs it stays locked away, and I do not simply accept that arrangement. I press for what can be examined, I use what the courts have already acknowledged about the instrument’s limits, and I keep the focus on the gap between how certain the number looks and how certain it is. I know the science this device relies on, and a machine that cannot fingerprint ethanol and is known to produce false positives is a machine whose output deserves scrutiny, not blind trust.
I started out as an Assistant Public Defender in Florida’s Thirteenth Judicial Circuit, in Tampa, and today I am one of six ACS-CHAL Forensic Lawyer-Scientists in Florida, with forensic training in how these instruments work. A breath result is an estimate produced by a machine, and I read its calibration history, its agreement checks, and the assumptions built into the number, so I can show a jury where it does not hold up. Learn more about my background.
Questions About Source Code
What is breath test source code?
It is the internal software that runs the Intoxilyzer 8000, controlling how it reads your sample, applies its checks, and produces a number. It is written and held by the manufacturer.
Can my lawyer get the source code?
Florida courts have generally required a specific showing of need before ordering it, and have held it cannot be reached through an ordinary out-of-state subpoena. Direct access has been difficult to obtain.
If the code is sealed, why does it matter?
The machine’s key decisions happen inside that software, out of view. Even without the code, its outputs and error logs show how it behaved, and the closed-source problem is a fair point for a jury.
Has a court said the machine can be wrong?
Yes. A Florida appellate court acknowledged the device can produce false positives because it reads only part of the infrared spectrum, even while denying access to the code.
Related: the main breath test defense page, how we challenge a breath test, and how the Intoxilyzer 8000 works.
This page is general information, not legal advice, and it does not create an attorney-client relationship. Breath testing in Florida is governed by Fla. Stat. 316.1932 and 316.1934 and the Florida Administrative Code chapter 11D-8. Procedures and rules change, and every case turns on its own facts. Past results do not guarantee a similar outcome.
