Challenging a search warrant

The Fourth Amendment states, “no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.” U.S. Amend. IV. A warrant is unlawful if it is not supported by probable cause, by oath or affirmation, or if it does not describe the place to be searched or person seized with sufficient particularity. There may be other available challenges, as a warrant may have been improperly executed in some way. For example, maybe the magistrate did not permit a “night search,” but the warrant was executed at night. Or, the information that provided the probable cause for the warrant might be “stale.” The two motions (which can also be combined) to consider filing in the event that a search warrant was executed, are a Motion to Quash and a Motion to Traverse.

Motion to Quash

If the warrant itself shows that there was no probable cause to conduct the search, then the warrant may be challenged by Motion to Quash. People v. Hobbs (1994) 7 Cal.4th 948. That challenge is not asking the court to look beyond the face of the warrant. The motion asks the court to look at the warrant itself and determine whether it presents a showing of probable cause. A Motion to Quash will necessarily fail unless the warrant on its face discloses no probable cause as a matter of law. Illinois v. Gates (1983) 462 U.S. 213. A Motion to Quash can also be made in instances where unlawfully obtained information provided the evidence that amounts to probable cause. People v. Weiss (1999) 20 Cal.4th 1073. If that is determined to be the case, the unlawfully obtained information must be excised from the warrant. If probable cause does not remain, then the warrant is not supported by probable cause and the evidence will be suppressed.

Motion to Traverse

Warrant applications are submitted by the officer, who also completes an affidavit in which the officer claims probable cause exists to search the person or place under investigation. Sometimes, other documents will show that there is a discrepancy between what the officer said in the search warrant affidavit and what the officer wrote in another document, like a police report. Or other testimony by the officer may lead a defense attorney to question the veracity of what was submitted to the magistrate in the affidavit supporting the search warrant. It is also possible that a witness for the defense can testify as to the claimed lies in the affidavit. If a warrant is challenged on this basis, it is called a Motion to Traverse. The defendant is asking the court to look beyond the face of the search warrant (called a “subfacial challenge”), and question the truthfulness of the contents of the affidavit. Franks v. Delaware (1978) 438 U.S. 154. Only if the defendant can make a prima facie showing of dishonesty in the motion, will the court grant a hearing on the matter (called a “Franks hearing”). An offer of proof is required, including witness declarations or other documents that show the dishonesty. Conclusory statements of untruthfulness will always fail.


People v. Panah (2005) 35 Cal.4th 395 [Franks hearing properly denied where defense motion consisted of “conclusory contradictions” of affiant’s statements and failed to show that the statements were material to PC determination];

People v. Luera (2001) 86 Cal.App.4th 513 [No showing made where affiant’s refusal to state that informant had claimed to see defendant’s computer did not contradict statement in affidavit that the informant had seen computer];

People v. Gibson (2001) 90 Cal.App.4th 371 [Franks hearing not required where omitted information neither added to nor detracted from the facts showing probable cause]

The procedure for preparing, filing, and arguing Motions to Quash and Traverse is complicated. These motions are difficult to win, because you are asking a court to find that a warrant was issued without probable cause, or that the officer submitted statements in reckless disregard for the truth. But it is important to challenge the search warrant where any of the above grounds exist. If the challenge is not made, an appeal after conviction on that basis is forfeited. A client may still be able to argue on a petition for writ of habeas corpus that counsel was ineffective for failing to make the challenge, but that is a tough showing to make. And a court does not have to hear a petition for a writ, but the court is required to hear a timely appeal.

About the Author

Lara J. Gressley

Lara Gressley

Lara Gressley has been an attorney for over two decades. She focuses her practice on criminal defense, DUI defense, and writs and appeals in state and federal court, and has worked on cases before the United States Supreme Court. Lara also lectures lawyers across California on various criminal defense topics.

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