AUSTIN – Texas law that allows police officers to take blood samples from suspected drunk drivers without a warrant is unconstitutional, the state’s highest criminal court ruled Wednesday.

The ruling could impact Texas’ “no refusal weekends,” including during the upcoming Thanksgiving holiday, when officers target suspected drunk drivers and subject them to mandatory breath and blood testing in the field. According to the ruling, law enforcement officers will need to have a warrant in hand before forcing suspects against their to submit to a blood alcohol content test.

“We hold that a nonconsensual search of a DWI suspect’s blood conducted pursuant to the mandatory-blood-draw and implied-consent provisions in the Transportation Code, when undertaken in the absence of a warrant or any applicable exception to the warrant requirement, violates the Fourth Amendment,” Judge Elsa Alcala of the Texas Court of Criminal Appeals wrote on behalf of the five majority opinion judges. Four members of the nine-judge court dissented.

The ruling stems from the 2012 case of David Villarreal, who was pulled over in Nueces County for a traffic violation. After refusing to perform sobriety tests in the field, Villarreal was arrested and taken to a local hospital to have his blood drawn against his will and without a warrant. The arresting officer said the move was legal because state law requires the taking of a breath or blood sample of anyone previously convicted two or more times of driving while intoxicated.

The state asked the trial judge to sentence Villarreal, who had been convicted of felony DWI in 2001 and 2005, to at least 25 years in prison. His attorney cited a 2013 U.S. Supreme Court ruling that said drawing a DWI suspect’s blood without a warrant violated the suspect’s constitutional right against unreasonable search and seizure.

The trial court agreed, saying the blood sample and the evidence it produced that Villarreal’s blood alcohol content of .16 was inadmissible. The state unsuccessfully appealed, kicking the case up to the Texas Court of Criminal Appeals, the state’s highest court for criminal cases.

Villareal’s attorney, Fred Jimenez, said that while he is pleased with the ruling, it will not mean police officers no longer will be allowed to take blood and breath samples against a DWI suspect’s will. They just need to ensure they have a warrant first.

“We’re not going to see the end of no refusal weekends, but the procedure has changed,” he said. “All it is, is a ruling that they cannot use the blood test that they obtained without a warrant. That’s all it is. They can still try my client. It’s a weaker case without that evidence. There’s a videotape of my client, and he looks good on the videotape.”

A spokesman said Nueces County District Attorney Mark Skurka was reading the opinion and had no immediate comment.