The Implied Consent Maze After a Wisconsin OWI Crash

 Posted on December 04, 2025 in DUI/OWI

OWI investigations in Wisconsin become far more complex when a crash is involved. Even when a driver is strapped to a stretcher, overwhelmed by pain, disoriented, or even unconscious, Wisconsin police may rely on the state’s implied consent law to take a blood sample. Unfortunately, from warrant requirements to unconscious driver exceptions, police officers frequently misapply the law. When a driver’s medical emergency takes precedence, steps can be skipped, decisions rushed, and the law misapplied.

This creates a real opportunity for a criminal defense attorney to challenge evidence, since blood draws from incapacitated drivers require a careful analysis of warrants, exigent circumstances, and whether the blood draw was voluntary or involuntary. Never assume that your OWI (346.63(5)(a)(a)) case is hopeless because of a high BAC. An experienced Racine County, WI criminal defense lawyer can begin preparing a comprehensive defense on your behalf.

Understanding the Implied Consent Law in Wisconsin Following an OWI Crash

Under Wisconsin’s implied consent law, every driver is deemed to have consented to chemical testing when lawfully arrested for OWI. Post-crash situations often fall outside the usual procedures, introducing new questions, including:

• The delayed arrival of the police
• Medical incapacitation of the driver
• Possible lack of the driver’s arrest before chemical testing
• Confusion on the part of the driver regarding the right to refuse chemical testing

As an aside, Wisconsin law officially uses the term OWI, which covers a broader definition of impaired driving, including operating a vehicle while impaired by alcohol or drugs. While it is similar in nature to DUI, and the terms are often used interchangeably, the use of "operating," rather than "driving," means that a vehicle does not have to be in motion for the driver to be charged with OWI.

How the "Lawful Arrest" Requirement is Often Overlooked After a Wisconsin Crash

Blood tests typically require a lawful arrest before implied consent applies. So, when a police officer requests a blood draw while the driver is unconscious before making a formal arrest, implied consent may not be valid. If the officer relies on hospital paperwork rather than arrest protocol, or uses statements like "We’re testing everyone involved," then implied consent may not apply. From the defense point of view, if there is no lawful arrest, implied consent does not apply.

Although Wisconsin once allowed warrantless blood draws from unconscious drivers, the 2019 case of Birchfield and Mitchell v. Wisconsin changed the landscape. While blood draws from unconscious drivers may be allowed, this is only true when exigent circumstances are present. Hospitals often draw blood for treatment, and then the police attempt to seize it via a subpoena. In most cases, no true exigency existed, the officer had time to obtain a warrant, or the medical draw lacked proper chain of custody.

When Must Police Obtain a Warrant for an OWI Blood Draw?

A warrant for a blood draw is always required unless the driver voluntarily consents to the blood draw, or exigent circumstances exist, which is rare in WI with the advent of e-warrants. Any evidence of deliberate delays by officers undermines claims of exigency. Since post-crash drivers are often medicated or in pain, this impacts the voluntary nature of a blood draw. Wisconsin law will evaluate whether the driver is on a medication that impairs comprehension, or whether consent was obtained while the driver was in the midst of treatment or in severe pain. Defenses include:

• Lack of lawful arrest
• Missing implied consent warnings
• A blood draw without a warrant or exigency
• Voluntary nature compromised by sedation or medical distress
• Improper chain of custody
• Police reliance on outdated automatic consent practices
• Medical blood vs. legal blood confusion

Contact a Milwaukee County, WI OWI Lawyer

If you were involved in an OWI-related crash, you should never assume the police followed Wisconsin’s implied consent rules to the letter. A Racine County, WI criminal defense attorney from Bucher Law Group, LLC can make sure your rights and future are protected. Attorney Bucher has personally handled hundreds of DUIs and will work aggressively on your behalf. Call 262-446-9222 to schedule your free consultation.