Is there a "shield of immunity" in the context of a search or seizure pursuant to a warrant?

Where the alleged Fourth Amendment violation involves a search or seizure pursuant to a warrant, the fact that a neutral magistrate issued the warrant is an indication that the officers acted with "objective good faith." United States v. Leon, 468 U.S. 897, 922-23 (1984). An exception allowing suit has been recognized when "it is obvious that no reasonably competent officer would have concluded that a warrant should issue." Molley v. Briggs, 475 U.S. 335, 341 (1986). The shield of immunity will be lost where the warrant was "based on an affidavit so lacking in indicia of probable cause as to render official belief in its existence entirely unreasonable." Leon, 468 U.S. at 923 (internal quotation marks omitted).