Re: Legal under the Patriot Act
Thanks for challenging me on this; I'll admit I was kinda hoping someone would.
It does not violate the First Amendment. Nothing in what has been revealed establishes or affects free exercise of religion, or abridges the freedom of the press, or prevents peaceable assembly to petition the Government. The fact that some people might self censor out of fear that an NSA analyst will see their activities in no way prevents those activities.
It does not violate the Fifth Amendment. What the NSA is doing does not result in holding a person for a capital or infamous crime; it could influence a grand jury toward issue of an indictment, but that's at least one remove from the collection and analysis of data. It does not subject an accused to double jeopardy (although other Federal actions arguably do so), and it surely does not compel any degree of self incrimination. Taking private property for public use also seems a nonstarter.
In National Association for the Advancement of Colored People v. Alabama, 357 U.S. 449 (1958) the Supreme Court held that freedom of association is essential to free speech, and therefore came under the fourteenth amendment.
The Fourteenth Amendment is almost identical to the Fifth Amendment, execept The Fifth covers the federal government and the Due Process clause of the Fourteenth covers states.
The weak point seems to be the Fourth Amendment. Things may be a bit less clear, but established law, for about 40 years, has it that telephone metadata such as has been compelled by subpoena from Verizon does not constitute unreasonable search under the Fourth Amendment. The government could be expected to argue that (a) internet metadata collection is not meaningfully different from telephone billing data. There may be issues with collecting all metadata rather than that of a particular group of named individuals, and there may be issues with probable cause; these issues seem not to have been determined yet by courts. As things stand, the best that can be said is that some people feel strongly that this collection exceeds Fourth Amendment limits.
As for the collected content (e. g., email bodies), the government doubtless will argue that collecting and storing the content does not constitute searching or seizure, but that search is done only when the stored data is retrieved for examination by an analyst. They might be able to persuade the courts of that, or in the event they cannot, that the efforts described to ensure exclusion of data that does not have at least one endpoint outside the US are adequate (possibly with further tightening).
Katz v. United States (1967) established the rule that the fourth amendment protections is extended if the person has a reasonable expectation of privacy recognized by society.
Smith v. Maryland (1979) said that pen registers where ok because Smith voluntarily disclosed the numbers he was calling to the phone company, and therefor had no reasonable expectation of privacy.
Which is more relevant is debatable, and considering the conflicting rulings the 1st/5th combo is probably more powerful.