[qutoe]Hopefully a SDMB lawyer-type will show up soon.
What am I, chopped livah?
There are two general aspects to the “right to privacy,” neither of which applies to teenagers living at home.
The first is the constitutional right to privacy that the U.S. Supreme Court has inferred from the U.S. Constitution. (There is no specific right to privacy listed in the Consitution.) This deals with the right to privacy from governmental intrusion. (The Constitution deals almost exclusively with the extension of government powers, and the limitations on government actions. It doesn’t address how one private citizen treats another.) If you want a general overview of Constitutional “right to privacy” thinking by the Supremes, Google “Lawrence v. Texas,” which is their last big case on it (striking down the Texas anti-sodomy law).
The second is the statutory right to privac, which in turn can be split into three broad categories (that I can think of off the top of my head). The first is a right to privacy in things like school records and medical records. The second is a right to privacy in your likeness, so that people can’t paste your famous face on a can of soda and sell it. (Though this is more properly construed as a right to publicity, as opposed to a right to privacy.) Both of these are grounded not in the constituion but in various laws passed by various jurisdictions that convey such rights. These laws in turn criminalize disseminating someone else’s private information, or likeness, in certain circumstances. The third is a right to notice before entry into a rental property by a landlord. Such laws exist in most states and bestow upon a tenant a right to privacy in his or her apartment or dwelling by requiring that the landlord given notice (usually 24 to 48 hours) before entering, in the absence of a compelling reason to enter immediately, such as an emergency. If a person rents a room, as opposed to an entire apartment or dwelling, that notice requirement still applies and the landlord can’t just go in and snoop around the room. And, of course, this right is also augmented by criminal law which prohibits anyone who doesn’t have your permission or any legal right to do so, from barging into your house (trespass, burglary, etc.).
The only one that even arguably might apply is requirement placed on a landlord to provide notice before entering. But that applies to tenants – you know, people who pay rent or other consideration in exchange for housing. A child, emancipated or not, is not a tenant unless he or she is paying rent or otherwise giving consideration in exchange for housing.
You ain’t a tenant. You’re a member of your parents’ household. You have only those rights to privacy that they choose to grant you. It might be a courtesy not to snoop through your stuff, but it’s not a requirement.