Does the Fourth Amendment protect a defendant's privacy interest when he makes incriminating statements to someone who is a government informant?

In defending the legality of the search, the government relies on case law which holds that a defendant's Fourth Amendment rights are not violated when he makes incriminating statements to someone who, unbeknownst to him, is a government informant. Hoffa v. United States, 385 U.S. 293, 302 (1966) (Fourth Amendment does not protect "a wrongdoer's misplaced belief that a person to whom he voluntarily confides his wrongdoing will not reveal it"); see also Smith v. Maryland, 442 U.S. 735 (1979) (defendant had no legitimate expectation of privacy in the numbers he dialed from his home telephone, which were monitored by the telephone company and turned over to the police). Perrin suggests that these cases are inapposite because they do not address the Fourth Amendment's greater protection of an individual's privacy interest in his property. We disagree with Perrin, and find the government's reasoning persuasive.