More detail here: http://en.wikipedia.org/wiki/Griswold_v._Connecticut
More detail here: http://en.wikipedia.org/wiki/Griswold_v._Connecticut
I was just trying to explain where the right to privacy comes from. It surprises most Americans that it isn't explicitly enumerated and is built up from several different amendments. That also means that it is far from universally agreed upon by legal scholars. It is also the reason that people push for a privacy amendment.
"The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized"
Thus, the government needs a warrant to open your mail, but not to inspect the envelopes you send your mail in - and this was spelled out in 1878 (Ex Parte Jackson). The scope of what courts have considered to be unreasonable searches is actually fairly narrow. I'm all for rethinking the fourth (or better, adding a 28th). But restore it to...what? How you imagined it when you were in grade school?
THE problem with pedantry is not that it is incorrect.