What is the test for probable cause de novo in a search warrant application?

We review the district court's ruling as to probable cause de novo. United States v. Elliott, 893 F.2d 220, 222 (9th Cir.), cert. denied, 111 S.Ct. 268 (1990); United States v. Dozier, 844 F.2d 701, 706 (9th Cir.), cert. denied, 488 U.S. 927 (1988). We must accept the district court's findings of fact relating to its review of the motion to suppress unless clearly erroneous. Id.

Although affidavits supporting search warrants are presumed to be valid, a defendant may challenge an affidavit by showing that it contains intentionally reckless or false statements and that the affidavit, purged of its false statements, would be insufficient to establish probable cause. Franks v. Delaware, 438 U.S. 154, 171 (1978).