California DUI's & The New McNeely Craze
The United States Supreme Court has recently handed down a decision that has had a direct impact on the way DUI cases are litigated. In Missouri v. McNeely, 133 S. Ct. 1552 (2013), the Supreme Court ruled that a warrantless blood draw from a DUI suspect may violate the driver's Fourth Amendment's protection against unreasonable searches and seizures.
Tyler G. McNeely was arrested for suspected drunk driving October 3, 2010. The arresting officer asked McNeely to submit to a breath test, which McNeely refused. The officer then transported McNeely to a hospital and instructed medical staff to draw a blood sample without McNeely's consent and without a warrant. During trial, McNeely's attorney moved to suppress the blood evidence, arguing that the blood sample was obtained in violation of McNeely's Fourth Amendment right against unreasonable search and seizures.
The State argued that the blood sample fell under the exigent circumstances exception, claiming that the evidence-the alcohol in McNeely's bloodstream-would be destroyed, or metabolized, during the time it would take to obtain a search warrant. The State also argued that drunk driving enforcement constitutes a compelling government interest.
The Supreme Court emphasized the importance of the Fourth Amendment, stating that "the importance of requiring authorization by a 'neutral and detached magistrate' before allowing a law enforcement officer to invade another's body in search of evidence of guilt is indisputable and great.' Johnson v. United States, 333 U.S. 10, 14-14 (1948).
However, they also made it clear that the exceptions to the 4th Amendment are prevalent and necessary. The Court also acknowledged that warrantless searches may be reasonable when 'there is compelling need for official action and no time to secure a warrant.'" Michigan v. Tyler, 436 U.S. 499, 509.
The Court recognized that there could not be a strict rule that could be applied to every instance, The Court reaffirmed that exigent circumstances must be evaluated under the totality of the circumstances, stating: "To determine whether a law enforcement officer faced an emergency that justified acting without a warrant, this Court looks the totality of circumstances." Brigham City v. Stuart, 547 U.S. 398, 406 (2006).
In fact there was a case in which the Court found that there was no warrant necessary to take a Defendant's blood. In Schmerber v. California, 384 U.S. 757, the warrantless blood test was deemed permissible as the "officer 'might reasonably have believed that he was confronted with an emergency, in which the delay necessary to obtain a warrant, under the circumstances, threatened the destruction of evidence.'" Quoting, Preston v. United States, 376 U.S. 364, 367 (1964). This does not mean that "mere dissipation of blood-alcohol evidence" is enough to support a warrantless blood draw. Missouri v. McNeely, 358 S. W. 3d 65, at 70; rather "exigency depends heavily on the existence of additional 'special facts,' such as whether the officer was delayed the need to investigate an accident and transport an injured suspect to the hospital." Id., at 70.
Ultimately, the Court ruled that while the natural dissipation of alcohol in the blood may support a finding of exigency in a specific case, it does not do so categorically. Whether a warrantless blood test is reasonable must be determined on a case-by-case basis on the totality of the circumstances McNeely v. Missouri, 569 U.S. __(2013).
2025 Update: The McNeely decision continues to play a critical role in California DUI defense cases involving blood draws. Courts still require law enforcement to justify warrantless blood tests based on specific facts, and failure to obtain a warrant may result in suppression of evidence depending on the circumstances of the stop and arrest.
2026 California DUI Blood Draw Update: Missouri v. McNeely Still Matters
More than a decade after the United States Supreme Court decided Missouri v. McNeely, the case continues to play an important role in California DUI investigations involving warrantless blood draws.
The Supreme Court’s ruling reinforced that law enforcement officers generally must obtain a warrant before conducting a non-consensual blood draw unless specific exigent circumstances exist under the totality of the circumstances.
Today, California DUI cases frequently involve:
- electronic warrant systems
- hospital blood draws
- DUI investigations involving accidents
- DUI drug investigations (DUID)
- unconscious driver allegations
- refusal allegations under California implied consent laws
Because modern technology now allows officers in many situations to obtain electronic warrants quickly, courts may closely analyze whether a true emergency existed at the time of the blood draw.
California courts continue to evaluate factors such as:
- how long obtaining a warrant would have taken
- whether an accident investigation delayed officers
- whether medical emergencies existed
- whether officers had access to electronic warrant procedures
- whether the driver consented to testing
In many DUI defense cases, blood draw procedures, warrant issues, and Fourth Amendment search concerns may still become important legal issues during litigation.
How McNeely Affects California DUI Defense Cases Today
The McNeely decision continues to impact DUI defense strategies involving:
- warrantless blood draws
- refusal allegations
- hospital blood testing
- suppression motions under Penal Code §1538.5
- constitutional search and seizure challenges
In some cases, defense attorneys may challenge:
- whether consent was voluntary
- whether a warrant was legally obtained
- whether officers properly followed blood draw procedures
- whether exigent circumstances truly existed
The outcome depends heavily on the facts of each case.
California Implied Consent Laws and Blood Draws
Under California’s implied consent laws, drivers lawfully arrested for DUI are generally required to submit to a chemical test.
However, implied consent laws do not automatically eliminate constitutional protections under the Fourth Amendment.
Courts may still evaluate whether:
- consent was valid
- force was used
- a warrant was necessary
- or the search was otherwise reasonable under the circumstances
DUI Blood Draw Cases in Southern California
Blood draw DUI investigations remain common throughout:
- San Bernardino County
- Riverside County
- Los Angeles County
- Orange County
These cases often involve detailed review of:
- police reports
- body-worn camera footage
- warrant records
- laboratory testing procedures
- timelines surrounding the arrest and investigation
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