The officers’ failure to knock-and-announce (really wait long enough) before entry does not invoke the exclusionary rule under Michigan v. Hudson. People v. Byers, 2016 Cal. App. LEXIS 1087 (4th Dist. Dec. 14, 2016):
The knock-notice requirement “is not easily applied.” (Hudson v. Michigan (2006) 547 U.S. 586, 589 (Hudson).) “[I]t is not easy to determine precisely what officers must do. How many seconds’ wait are too few? Our ‘reasonable wait time’ standard [citation], is necessarily vague.” (Id. at p. 590.) “[W]hat constituted a ‘reasonable wait time’ in a particular case, [citation] (or, for that matter, how many seconds the police in fact waited), or whether there was ‘reasonable suspicion’ of the sort that would invoke the Richards exceptions, is difficult for the trial court to determine and even more difficult for an appellate court to review.” (Hudson, at p. 595.)
In Hudson, the Supreme Court held that the exclusionary rule is not the appropriate remedy for a violation of the knock-notice requirement. (Hudson, supra, 547 U.S. at pp. 590, 599.) In part, this is because the exclusionary rule and the knock-notice requirement serve different purposes. The exclusionary rule protects against unlawful warrantless searches. (Id. at p. 593.) The knock-notice requirement, in contrast, seeks to prevent violence (due to an inhabitant being taken by surprise), property destruction (e.g., of a door), and loss of an occupant’s privacy and dignity (caused by an outsider’s sudden entry). (Id. at p. 594.) When officers have a search warrant, the knock-notice requirement is not intended to prevent “the government from seeing or taking evidence described in [the] warrant.” (Ibid.) Similarly, when a search is conducted pursuant to an absent co-tenant’s consent, the purposes of the knock-notice requirement (Duke, supra, 1 Cal.3d at p. 321) do not include preventing law enforcement from seeing or seizing evidence pursuant to the consent exception. Furthermore, the exclusionary rule is applicable only “‘where its deterrence benefits outweigh its “substantial societal costs . . . .”‘” (Hudson, at p. 591.) The costs of recognizing the exclusionary rule as a remedy for knock-notice violations would include the release of dangerous criminals into society, inordinate wait times before entry and consequent destruction of evidence, and a “constant flood of” litigation about hard-to-apply standards such as what is “a ‘reasonable wait time'” or whether officers had a “‘reasonable suspicion.'” (Id. at p. 595.) These substantial societal costs outweigh the knock-notice requirement’s minimal deterrence value (id. at p. 596), especially because an officer’s violation of the rule is deterred by the risk of civil suit and/or internal police discipline (id. at pp. 597-599).