In some breath cases, nothing about the person matches the number. The driving was clean. The speech was clear. The field exercises went well. And then the machine reported a level that says you should have been visibly impaired. That contradiction is the disconnect defense.
It is one of the strongest things a jury can be shown, and it really turns on one move: the State’s answer that a seasoned drinker hides impairment, the tolerance argument. This page is about meeting that argument and showing where it fails. The broader contradiction between the number and the rest of the evidence lives on the miles apart defense page.
What the Disconnect Is
A breath result that is truly accurate should line up with how a person looked and performed. When someone drove well, followed instructions, stood steady, and spoke normally, a high reading sits at odds with all of it. The disconnect is that mismatch, and it is a fair reason to ask whether the number, and not the person, is the unreliable part of the case.
Tolerance can help explain surface behavior like speech and balance. It does not improve divided attention, following directions, or involuntary eye movement. When a person did well on those, the State’s tolerance theory loses its footing.
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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 State’s Tolerance Argument
When the disconnect is obvious, the State often turns to tolerance. The argument is that a heavy, regular drinker learns to mask the effects of alcohol, so a person can look sober at a high level. There is some truth to tolerance for certain surface behaviors, like speaking without slurring or standing without swaying.
Where Tolerance Runs Out
Tolerance has a ceiling. A person can learn to talk and balance, yet the field sobriety exercises are built to test divided attention, the ability to follow instructions and do two things at once, which learned tolerance does not fix. Involuntary signs, like the eye movement an officer checks for, are outside anyone’s control. When someone performed well across those measures, tolerance cannot explain the gap, and the high number stands alone and unsupported.
Two questions, not one
It helps to remember that a Florida DUI is built on two separate questions, because the disconnect lives between them. Under section 316.193, the State can try to prove that your normal faculties were impaired, or it can try to prove a 0.08 reading, and those are not the same thing. The disconnect defense works in the gap. It takes a high number from a machine and sets it beside a person who drove without trouble, answered questions clearly, and moved through the roadside exercises like someone in control of themselves. The State’s usual reply is tolerance, the idea that a seasoned drinker can look fine at a high level, and that reply is a claim it has to back up rather than a fact it gets for free. When the everyday evidence of normal function is strong, tolerance gets harder to sell, and a jury is left with a real reason to doubt that the number told the truth about the person in front of them.
Why This Matters in Your Case
We build the disconnect by gathering everything that shows how you really were: the driving, the bodycam, the field exercises, the breath room video. Then we meet the tolerance argument head on with the parts of the record tolerance cannot touch. A jury that watches a capable, coordinated person is well positioned to doubt a number that says otherwise. This works closely with the miles apart defense.
When the indicators of impairment are all absent and only the machine says otherwise, the number is the outlier, not the person.
The Evidence That Builds the Disconnect
The disconnect is drawn from the same record the State will use. Clean, lawful driving with no bad pattern. Clear speech with no slurring on the bodycam. Steady performance on the field exercises. An alert, oriented person who followed instructions. Each of these is an indicator of impairment that came back negative. Stacked together, they describe someone who does not match a high breath number, and the more of them that line up, the harder it is to explain the number away.
When the Number Is the Outlier
The State’s answer is usually tolerance, the idea that an experienced drinker can hide a high level. That argument has limits, and it cannot stretch to cover a person who shows no impairment anywhere in the record. When every human indicator says one thing and only the instrument says another, the reasonable conclusion is that the instrument is the outlier. We reinforce that with the science of why the reading can be wrong, the partition ratio, breath temperature, and the margin of error, so the jury has a concrete reason the number, and not the person, is the thing that does not fit.
When a machine says one thing and a person’s own behavior says another, I build the case around the disconnect and make the State explain it away rather than assume it. I gather the driving, the video, and the field exercises, and I hold them up next to the number, because a jury can see a person functioning normally and weigh that against a reading from a device with all the assumptions we challenge. I know how to make that contrast land, and I do not let a single number quietly overrule everything a jury can watch with their own eyes.
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 the Disconnect Defense
What is the disconnect defense?
It is the argument that your appearance and performance do not match a high breath reading. When the driving, speech, and field tests all look sober, the contradiction gives a jury a reason to doubt the number.
What is the tolerance argument?
It is the State’s response that a regular drinker can mask the effects of alcohol and appear sober at a high level. It can explain some surface behavior, like clear speech and steady balance.
How do you answer a tolerance argument?
Field sobriety exercises test divided attention and following instructions, and some signs like involuntary eye movement are not controllable. Doing well on those is something tolerance does not explain.
Do I need an expert for the disconnect defense?
Often the video and your performance carry the argument on their own, though a forensic review can strengthen why the breath number is unreliable.
What is the disconnect defense in a breath case?
It is the contrast between a high breath number and a person who drove, spoke, and moved normally. Florida’s DUI law asks both whether your normal faculties were impaired and whether you were at 0.08, and strong everyday evidence of normal function gives a jury reason to doubt that the number captured the truth. The State’s tolerance argument is a claim it has to support.
Related: the main breath test defense page, how we challenge a breath test, and the miles apart defense.
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.
