In some states, you have the right to refuse a breath test for alcohol, but Iowa state code effectively bars this. You are “deemed to have given consent” to a test when you get into your vehicle. These can be blood tests, breath tests, urine tests or chemical tests.
The police cannot ask you to take a test for no reason. There must be reasonable grounds to think you have been operating a motor vehicle while under the influence of either drink or drugs.
In certain circumstances, the police can carry out a test without your permission. For example, if you are in a crash where people are injured or killed. Or if you are unconscious after an accident.
What happens if I refuse?
If you refuse to submit to a test, your license will be revoked for one year. It will be revoked for two years if you have refused before.
The refusal also removes your right to a deferred judgment. If a judge offers you this option, they will dismiss the operating while intoxicated (OWI) charge if you complete the required probation, so you may not want to lose possibility by refusing.
Perhaps you feel that the officer has no reason to demand a Breathalyzer test. You may be right — but you can challenge the reasonableness of the request through your attorney in court.
By far, your best option is to understand the alcohol limit and avoid drinking before driving. In Iowa, the blood alcohol content limit is 0.08%. It is lower for commercial drivers at 0.04%, and lower still for under 21s at 0.02%. Seek legal help to understand your options if charged with OWI.