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How Do Implied Consent Laws Affect Me?


Implied consent is, in simple terms, an agreement to do something which is not expressly stated by the person so agreeing, but can be inferred from his actions, i.e., when a person does not expressly agree to a thing, but it can be reasonably drawn from his actions that he agrees; he is deemed to have given his implied consent.

The laws of the state of Idaho state that any person who drives a motor vehicle in the state is presumed to have consented to evidentiary testing for Blood Alcohol Concentration or presence of drugs or other substances which can cause impairment. The test must be administered at the request of a peace officer upon reasonable suspicion that a person who is driving or in control of a vehicle is impaired by alcohol or some other substance to come under its implied consent provisions.

In simple terms, any driver in Idaho pulled over by a law enforcement agent who reasonably suspects him of driving while intoxicated has already consented to a breathalyzer test or blood test to determine his level of impairment.

Does This Mean You Can’t Refuse a BAC Test?

The short answer is no; you can refuse to take a breathalyzer or blood test. According to a report given by the National Highway Transport Safety Administration (NHTSA) on data collected from 37 states, the District of Columbia and Puerto Rico in 2005, many drivers pulled over on suspicion of DUI, ranging from 2.8% in Delaware to 81% in New Hampshire, refused BAC testing.

Your DUI attorney has greater leverage if there is no breathalyzer test result. However, refusing a formal evidentiary test is not without its consequences.

Consequences of Refusing Evidentiary Testing

After a peace officer stops a motorist on suspicion of driving while intoxicated, he has the option of refusing a breathalyzer test. If he chooses to, he violates the implied consent laws applicable in Idaho and may face the following consequences:

  1. A fine of two hundred and fifty dollars ($250)
  2. Compulsory installation of a state-approved ignition lock device on all motor vehicles operated by him for one year following the end of the suspension period. He will be mandated to pay for the installation.

The law requires that peace officers inform motorists of these consequences while he requests for the test.

Are Implied Consent Laws Constitutional?

Implied consent sounds like it should be illegal, but according to the United States Supreme Court, it is constitutional. In Birchfield v. North Dakota, a 2016 apex court decision, it was held that the refusal to take a blood test after a DUI arrest is not a separate crime. Such an imposition was found to contravene the Fourth Amendment protection against unjustifiable searches and seizures due to its invasive nature. The court, however, differentiated a blood test from a breathalyzer test, confirming the legality of implied consent laws as regards breathalyzer tests. It was further stated that to administer a blood test, a peace officer must obtain a warrant, but a breath test can be administered without one.

Are There Any Remedies?

Refusing a BAC test is not without its consequences. However, the law provides that a person who refuses BAC testing can apply to the courts within seven days to determine why he refused the test; if it is found that there was no reasonable cause to pull the driver over and ask him to take the test or that the test  infringed on his civil rights, the punishments would be waived.

It is advisable to speak to a Boise DUI attorney as soon as possible to help you file the request, and prepare and argue your case.

What Does This Mean for Me?

Idaho State law makes it a crime for you to refuse BAC testing due to its implied consent laws. While the US Supreme Court has decided that refusing a blood test cannot be treated as a separate crime, you can still be prosecuted for refusing a breath test. Furthermore, a blood test can be forcefully administered if the police officer obtains a warrant, and though refusal cannot be treated as a separate crime, it can still impede your case in the main DUI trial.

There are many things to consider before choosing to refuse BAC testing; you could face harsh penalties including losing your license and paying for the installation of an Ignition Interlock Device on your car which can cost up to $1000. It is essential to understand the law before making a decision, so you should speak to a Boise DUI lawyer who is an expert on Idaho DUI laws and can guide you to the best course of action.