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Does an Illegible Signature On a Warrant Invalidate the Results of a DWI Blood Test?

If a police officer suspects you of drunk driving, they can ask you for consent to perform a blood test. Should you refuse–as is your constitutional right–the officer must then obtain a search warrant before proceeding any further. Texas law requires the warrant to be signed by a magistrate “in clearly legible handwriting or in a typewritten form with the magistrate’s signature.”

Court of Criminal Appeals: Officer Acted in “Good Faith,” Despite Bad Warrant

The Texas Court of Criminal Appeals recently addressed a scenario where a magistrate’s signature on a DWI-related search warrant was not legible. Two lower courts held the illegible signature invalidated the warrant. But the Court of Criminal Appeals disagreed, holding that despite the defect, the officer acted “in good faith” relying on the warrant.

Here is some additional background on the case, State v. Arellano. A police officer in Victoria County arrested the defendant on suspicion of DWI. The officer then submitted a “probable cause” affidavit to a local magistrate and asked for a search warrant to conduct a test of the defendant’s blood-alcohol content (BAC). The warrant returned to the officer contained what the Court of Criminal Appeals described as a “cursive signature,” but the “magistrate’s name was not typed or handwritten anywhere on the warrant.”

After the blood test came back, prosecutors formally charged the defendant with DWI. Before the trial court, the defendant asked the judge to suppress the results of the drug test. He noted the warrant was invalid due to the “illegible” signature of the magistrate. The prosecution did not contest this fact, instead arguing the officer was permitted to rely on the defective warrant “in good faith.”

As noted above, both the trial judge, and later an intermediate court of appeals, rejected the prosecution’s good-faith argument. Traditionally, courts have allowed prosecutors to introduce evidence that was technically obtained in violation of a defendant’s constitutional rights if the officer who collected said evidence acted in “good faith.” In this case, the lower courts found this exception could not be applied given the search warrant itself was invalid on its face.

But the Court of Criminal Appeals said the good-faith exception did apply. More to the point, the fact the warrant contained an illegible signature “did not preclude application” of the exception. The lower courts relied on a 2017 decision from the Court of Criminal Appeals, McClintock v. State, in holding that the good-faith exception could not apply to this case. The McClintock case, however, “involved a lack of probable cause to support a search warrant” rather than a “search warrant’s defective form,” the Court of Criminal Appeals observed.

Indeed, the Court pointed to another one of its own decisions from 1997, Dunn v. State, in which it applied the good-faith exception “to an arrest warrant that had no magistrate’s signature whatsoever.” Applying similar reasoning to the Arellano case, the Court said there was no reason to disregard the defendant’s blood test due solely to the illegible signature on the search warrant.

Speak with a Houston DWI Defense Lawyer Today

There are a number of small procedural details that matter when it comes to a drunk driving case. If you are facing DWI charges and need legal assistance from a qualified criminal defense attorney, contact the Law Offices of Tad Nelson & Associates in Houston, Galveston or League City today. Call (281) 280-0100