The Texas Court of Appeals told local police officers last month that when the US Supreme Court says warrantless blood draws from motorists are unconstitutional, that means they need to get a warrant to perform a blood draw. Hurst Police Officer Brian Charnock did not believe the McNeely ruling applied to him as he ordered Laura Ann Swan to pull over in February 2012.
Officer Charnock had received a tip that the car belonging to Swan was swerving on the highway, so he drove to her home. Before arriving, he allegedly saw Swan fail to signal a turn. He conducted a traffic stop during which Swan refused to perform sobriety tests and denied drinking anything, leaving the officer with no concrete evidence beyond the smell of alcohol.
Officer Charnock decided to arrest Swan for driving under the influence of alcohol (DUI), but she refused a breathalyzer test. Under state law, police have the duty to forcibly perform a breath or blood test if the officer has reliable information that the suspect has been convicted twice before of DUI — and Swan was a repeat offender. So without obtaining a warrant, Officer Charnock had Swan’s blood forcibly taken.
The appellate panel reasoned that a state law cannot be used to overturn a constitutional interpretation of the Supreme Court.
“While section 724.012 requires the taking of a specimen in those circumstances, the section does not expressly authorize the taking to occur without a warrant,” Chief Justice Terrie Livingston wrote for the appellate court. “Courts of appeals, including this court, have repeatedly applied the holding from Villarreal to likewise conclude that a warrantless search and seizure of a defendant’s blood purported to be justified only by section 724.012’s requirements is unconstitutional.”
Prosecutors tried to save the conviction by arguing even if the warrantless blood draw was unconstitutional, the evidence so taken should be admitted in court. The purpose of suppressing evidence is to deter bad police conduct, but here, they argued, Officer Charnock was doing what he thought was the right thing to do. The argument did not work.
“In other words, the state argues that Officer Charnock’s good faith in applying what he believed the law to be at the time of the search precludes suppression of the blood test results even if the search and seizure violated appellee’s constitutional rights as determined by later decisions,” Justice Livingston wrote. “But as the state recognizes, we have considered and rejected this argument.”
A copy of the decision is available in a 75k PDF file at the source link below.
Source: 
Texas v. Swan (Court of Appeals, State of Texas, 1/21/2016)