I hear a lot of people ask why they can’t just cooperate with police to prove that they are “okay” to drive. By “cooperate,” I mean submitting to what the police who have stopped you are requesting of you. Having said that, there are some things for which you must “cooperate” and some things for which you do not.
After being stopped, you must provide your license and registration. If the officer requests that you exit your car, you must do so. If an officer tells you that you must submit to a breath or a blood test after being arrested, you must do so. For these things, you must “cooperate.”
The police who stopped you will ask questions aimed at obtaining incriminating evidence. “Where are you coming from?” “Where are you going?” “Have you been drinking?”
First off, lying will only get you in more trouble. The 5th Amendment was created so that you wouldn’t have to lie. However, you do not have to “cooperate” in answering the officer’s questions either. Even if you don’t think what you say will incriminate you, it might. Just keep your mouth shut.
The officer will ask you to “cooperate” by performing field sobriety tests. Don’t think that by “cooperating” in agreeing to perform the field sobriety tests and thinking you’ll pass is in your best interest. The tests are optional and you do not have to “cooperate” in performing them, even if you think you’ll pass. There is no proving that you are okay to drive. The officer likely already believes that you are drunk and will interpret your performance on the field sobriety tests as such.
The officer will ask you to “cooperate” by submitting to a pre-arrest breathalyzer (known as a preliminary alcohol screening test). Like the field sobriety tests, this is optional and you do not have to “cooperate” in submitting to it. Contrast this from what I said earlier. You must “cooperate” and submit to chemical test, which can include a breathalyzer, after you have been arrested.
I would also be remiss if I didn’t distinguish between being “cooperative” and being “polite.” While you do not have to “cooperate” with several of the officer’s requests as stated above, it is in your best interest to be “polite.”