Members of both the House and the Senate have called for the release of documents that do precisely what these do: outline how and when the NSA might collect domestic data, and how it tries not to. One of the points these documents raise is that, given the breadth of the agency's collection efforts, collecting data from Americans almost necessarily occurs. According to a separate, one-paragraph document The Guardian has seen, however, the FISC found the procedures described by Holder to be "consistent with US law and the fourth amendment."

The Guardian's Glenn Greenwald provides an overview:

The top secret documents published today detail the circumstances in which data collected on US persons under the foreign intelligence authority must be destroyed, extensive steps analysts must take to try to check targets are outside the US, and reveals how US call records are used to help remove US citizens and residents from data collection.

To avoid including Americans (technically, "US persons") in its sweeps, the NSA asks several questions about a target.

If the person passes that test, the NSA further examines the data it collects for signs that the person might or might not be an American, including checks against known phone numbers and IP address data. Or if the person happens to be a "buddy" of a foreign intelligence official.

Should the data not pass these tests — if, in other words, the NSA believes the data does pertain to an American — it doesn't necessarily have to get rid of the data. Greenwald outlines three examples in which the NSA can keep and use data collected from Americans.

Retain and make use of "inadvertently acquired" domestic communications if they contain usable intelligence, information on criminal activity, threat of harm to people or property, are encrypted, or are believed to contain any information relevant to cybersecurity;

Preserve "foreign intelligence information" contained within attorney-client communications;

Access the content of communications gathered from "U.S. based machine[s]" or phone numbers in order to establish if targets are located in the US, for the purposes of ceasing further surveillance.

The point about encryption was immediately isolated as significant by observers, like the Electronic Frontier Foundation's Hanni Fakhoury.

Per leaked FISA docs, using encryption is equated with criminal activity: http://t.co/k3IFHV3n0D — Hanni Fakhoury (@HanniFakhoury) June 20, 2013

And, as attorney Amie Stepanovich noted, the NSA keeps email addresses and phone numbers it knows belong to Americans in order to identify other people as being American or not.

Incidentally, if the NSA can't figure out whether or not a person is an American, it is allowed to assume that the person is not, according to Greenwald.

"In the absence of specific information regarding whether a target is a United States person," it states "a person reasonably believed to be located outside the United States or whose location is not known will be presumed to be a non-United States person unless such person can be positively identified as a United States person."

It is not clear whether or not these are the "minimization procedures" still in effect for the NSA's surveillance systems. The compliance systems appear to comport with what was described by NSA head Keith Alexander and the FBI during a hearing this week. Since a previous FISA document obtained by Snowden apparently came from a batch of training documents, it's possible that these documents were similarly available to train new NSA employees on how and when to use the tools.