A police officer pulls you over on the way home from a friend's house. You drifted over the center line, he says. He wants to give you a breath test to see if you're under the influence.
You're skeptical right away. It's one in the morning, and you're not even sure you drifted over the line. Was the officer just looking for excuses to pull anyone over and check one's blood alcohol concentration (BAC) because it's more likely that drunk drivers are out at night?
Either way, you go through with the test, knowing you don't feel impaired. You should be fine.
Then the breath test shows a BAC of .10, over the legal limit. The cuffs go on, and you're already trying to figure out how it's possible. Could the breath test be inaccurate?
People often act like a breath test provides perfect scientific results, but that's simply not the case. Below are five critical reasons why those results could be inaccurate.
1. It wasn't calibrated.
A breath test can't be set up initially and then expected to work for years. Officers must test and calibrate devices on a regular basis.
2. The officer made a mistake.
Human error is a huge issue when dealing with breath tests. Maybe that officer who pulled you over was a rookie, using the test for the first time. How confident did he look that he was doing it properly?
3. Outside factors triggered the test.
Experts warn that things like paint fumes and chemical adhesives can trigger the test. What exactly did you have in the car with you when that test said you were over the legal limit?
4. Software bugs interfered.
You know from using cellphones and laptops that software isn't perfect. Problems come out of the blue, with no warning. The breath test also uses software to produce results, and even a small bug could invalidate those results.
5. Other substances gave a false positive.
Did you use mouthwash right before getting in the car? Are you using any medications, like one for a toothache? These types of things have set tests off before. Carefully consider anything you may have used or consumed, other than alcohol, that could make it look like you had too much to drink.
Of course, every case is different. The key, though, is to remember that you do have rights and legal options when things don't seem to add up. Don't assume the breath test has to be right or that the police officer can't be wrong -- no matter how confident he or she seems. These examples show that there is plenty of gray area, and it's critical to keep that in mind when you're surprised by the breath test results.