In what circumstances will a prosecutor obtain a search warrant to search a house?

In Bumper v. North Carolina (1968) 391 U.S. 543, 88 S.Ct. 1788, 20 L.Ed.2d 797 police officers gained admittance to a residence when one of them announced that 'I have a search warrant to search your house.' (Id. 391 U.S. at p. 546, 88 S.Ct. at p. 1790.) The prosecutor did not rely upon a warrant to justify the search, however, but upon the consent of the resident. The court, in holding the search to be unlawful, stated: 'When a law enforcement officer claims authority to search a home under a warrant, he announces in effect that the occupant has no right to resist the search. The situation is instinct with coercion--albeit colorably lawful coercion. Where there is coercion there cannot be consent.' (Id. 391 U.S. at p. 550, 88 S.Ct. at p. 1792.)