What is the current state of the law on the right to search a person's home for the purpose of obtaining a search warrant?

"What a person knowingly exposes to the public, even in his own home or office, is not a subject of Fourth Amendment protection." Katz v. United States, 389 U.S. 347, 351 (1967). By inviting strangers off the street into his home, Couch exposed all of the sights, sounds and smells that could be detected from the inside of his living room and bathroom, which he permitted the officers to use. The officers therefore committed no Fourth Amendment violation in detecting the scent of cultivated marijuana, nor in observing of a heavy masking aroma of incense. This information was properly included in the warrant affidavits.

B. We review the issuance of a search warrant only to determine whether the magistrate had a substantial basis for concluding that probable cause existed. The magistrate must make a "practical, common sense decision whether, given all the circumstances set forth in the affidavit ... there is a fair probability that contraband or evidence of a crime will be found in a particular place." Illinois v. Gates, 462 U.S. 213, 238 (1983).