McCarthy v. Commonwealth (2021): Birchfield and...

McCarthy v. Commonwealth (2021): Applying Birchfield to Kentucky DUI Blood Test Refusals

McCarthy v. Commonwealth, 628 S.W.3d 18 (Ky. 2021), applied the U.S. Supreme Court’s landmark decision in Birchfield v. North Dakota, 579 U.S. 438 (2016), to Kentucky DUI law. The case addressed the constitutional limits on warrantless blood testing in DUI investigations and the consequences of blood test refusal — issues that arise constantly in DUI cases across Lexington, Louisville, and throughout the Commonwealth.

The Facts of the Case

The defendant was arrested for DUI in Kentucky. During the DUI investigation, law enforcement sought to obtain a blood sample from the defendant without a warrant. The defendant refused the blood test. The prosecution sought to use the defendant’s refusal as evidence of guilt at trial and to impose enhanced penalties for refusal under Kentucky’s implied consent law, KRS 189A.103.

The Legal Issue

The question was how the U.S. Supreme Court’s Birchfield decision — which held that the Fourth Amendment permits warrantless breath tests incident to DUI arrest but does not permit warrantless blood tests — applies to Kentucky’s DUI enforcement and implied consent framework.

The Court’s Holding and Reasoning

The Kentucky Supreme Court applied Birchfield’s framework, holding that because blood tests are significantly more intrusive than breath tests — involving a physical piercing of the skin and the extraction of a bodily fluid that can reveal far more information than blood alcohol content alone — they require either a warrant or a valid exception to the warrant requirement. A DUI arrest alone does not constitute an exception that permits a warrantless blood draw.

The Court addressed the interplay between Birchfield and Kentucky’s implied consent statute, KRS 189A.103, which provides that any person who operates a motor vehicle in Kentucky is deemed to have consented to chemical testing. The Court held that while the implied consent statute remains valid for breath tests, law enforcement generally must obtain a warrant before compelling a blood draw, absent exigent circumstances or actual voluntary consent.

The Court also addressed whether a defendant’s refusal to submit to a blood test can be used as evidence at trial, balancing the defendant’s Fourth Amendment rights against the state’s interest in DUI enforcement.

Impact on Kentucky Criminal Defense Today

McCarthy is essential reading for every DUI defense attorney in Lexington, Louisville, and across Kentucky. The decision reinforces that warrantless blood draws in DUI cases are presumptively unconstitutional and that law enforcement must generally obtain a warrant before compelling a blood test.

Defense strategies include: challenging warrantless blood draws as Fourth Amendment violations, filing motions to suppress blood test results obtained without a warrant or valid consent, challenging the voluntariness of consent to blood testing, and arguing that implied consent alone does not satisfy the Fourth Amendment’s warrant requirement for blood draws.

Under KRS 189A.010, DUI penalties escalate significantly with higher BAC levels and repeat offenses. Suppressing blood test results can dramatically alter the outcome of a DUI case.

How Clark + Harris Uses This Precedent

At Clark + Harris, our DUI defense attorneys in Lexington and Louisville aggressively challenge warrantless blood draws in DUI cases. We understand the constitutional framework established by Birchfield and McCarthy and use it to protect our clients’ Fourth Amendment rights. When blood evidence was obtained unconstitutionally, we fight to suppress it.

Understanding Kentucky case law is what separates experienced criminal defense attorneys from the rest. If you are facing DUI charges involving a blood test, call Clark + Harris at 859-474-0001 to discuss your defense options.

Frequently Asked Questions

How soon should I contact Clark + Harris after being charged in Kentucky?

As soon as possible. Early representation protects your rights during questioning, preserves evidence, and often leads to better outcomes. Call 859-474-0001 — we respond promptly to new inquiries.

Does Clark + Harris represent clients throughout Kentucky?

Yes. We represent clients in all 120 Kentucky counties, both state District and Circuit courts, and federal courts in the Eastern and Western Districts of Kentucky.

What happens during a free consultation with Clark + Harris?

We review the specific charges and evidence, discuss available defenses, explain the likely process in the relevant court, and give you a clear roadmap of next steps — at no cost to you.

Related Resources

If this information applied to your situation, the following Clark + Harris guides may also be helpful:

McCarthy v. Commonwealth (2021): Birchfield and Warrantless Blood Tests in Kentucky DUI Cases