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Chapter 321J of the Iowa Code provides details on the crime of operating while intoxicated. Within this chapter, the law defines the crime of impaired driving and establishes special rules for underaged and commercial drivers. The law also sets out penalties for OWI convictions. Penalties may include license revocation, surrender of vehicle registration or motor vehicle impoundment.
How Iowa’s DUI Laws Define the Offense
Iowa Code Section 321J.2 defines the offense of operating while under the influence of alcohol or a drug or while having an alcohol concentration of .08 or more (OWI).
You can be convicted of the offense of OWI in Iowa if you operate a motor vehicle while any of the following are true:
- You are under the influence of an alcoholic beverage or other drug or a combination of both.
- You have a BAC of .08 or higher.
- You have any amount of a controlled substance present and measurable in a blood or urine test.
You need to meet only one of these criteria to be eligible for conviction. While having a high BAC or a detectable amount of drugs in your system can make it easier to prove a case against you, it is not necessary to secure a conviction if law enforcement can otherwise prove you were under the influence.
DUI Definitions for Commercial and Underage Drivers
There are special DUI rules for commercial and underage drivers.
Iowa Code Section 321J.2A prohibits underaged drivers from operating a vehicle with a BAC of .02 or higher. Their driver’s license must be revoked if their BAC is found to be above this limit. This is typically referred to as a zero-tolerance rule.
Iowa Code Section 321.208 makes clear that driving with a BAC of .04 or higher is unlawful for those operating commercial vehicles. Commercial vehicle operators can face a one-year disqualification from operating commercial vehicles, among other penalties, if their BAC exceeds this limit.
Iowa’s BAC Limit and Per Se DUIs
In some cases, prosecutors must specifically prove impairment to secure a conviction. However, under DUI per se laws, a driver who has a BAC above a certain threshold is automatically classified as impaired. The only proof necessary is the BAC test results.
In Iowa Code Section 321J.2, the law says you are operating while under the influence if your BAC is .08 or higher. “Per se” means “by itself or on its own,” and this statute makes clear that a .08 BAC alone is sufficient for a DUI conviction.
Mitigating and Aggravating Circumstances of an Iowa DUI
Aggravating factors are circumstances that result in more serious penalties. When they are present you are considered to have committed a more serious violation of the law.
In Iowa, some aggravating factors include:
- a high BAC (above .15)
- repeat offenses
- driving impaired with a child passenger
- causing an accident that results in injuries or fatalities
On the other hand, mitigating factors provide some justification or excuse for the behavior. If you are a first-time offender and are willing to enter into a substance abuse treatment program, these are mitigating factors that can result in less severe penalties.