When is Section 3109 of the Civil Code requiring a police officer to knock on a door to a person's home?

Section 3109 reflects " 'the reverence of the law for the individual's right of privacy in his house,' " a reverence that is " 'deeply rooted in our heritage and should not be given grudging application.' " Sabbath v. United States, 391 U.S. at 589, 88 S.Ct. at 1758 (quoting Miller v. United States, 357 U.S. at 313, 78 S.Ct. at 1198). Accordingly, we adhere to the principle implicit in our prior cases that exigent circumstances may excuse noncompliance with the knock-and-announce requirement only where (1) the officers believe there is an emergency situation and (2) their belief is objectively reasonable. To excuse noncompliance either when the officers had no thoughts of emergency or when there was no reasonable basis for such thoughts would inappropriately compromise the privacy interest to be protected.

B. The Evidence