The US National Security Agency (NSA) has an informal agreement whereby it shares raw intelligence data with Israel's spy unit.
A document leaked by US whistleblower Edward Snowden to The Guardian outlines a memorandum of understanding between the NSA and Israel SIGINT National Unit (ISNU) on how information shared should be handled to protect US persons.
As part of the background to the memo, the document confirms that the NSA "routinely sends ISNU minimised and unminimised raw collection ... as part of the SIGINT relationship between the two organisations. This mutually agreed upon exchange has been beneficial to both NSA's and ISNU's mission and intelligence requirements".
Although the term "US persons" is used throughout the document to generally mean a citizen or resident of the United States, the memo notes that all of the procedures used to protest US persons should also apply to UK, Australian, Canadian, and New Zealand persons due to the NSA's agreements with these countries.
Raw SIGINT is defined in the document as information that has not yet been evaluated for foreign intelligence, and "includes, but is not limited to, unevaluated and unminimised transcripts, gists, facsimiles, telex, voice and digital network intelligence metadata, and content".
Minimisation is further referred to in the document as the process of only including US persons' information if it is needed to understand the intelligence.
While this indicates that the US sends ISNU raw intelligence data on US persons without first assessing what is being sent, the memo attempts to place restrictions on Israel's use of the information.
In particular, ISNU is not permitted to use the data to intentionally target US persons and do its own interception of communications to or from a US person. The document also limits access to the data to properly trained and cleared ISNU members.
When ISNU needs to share intelligence information outside of its own unit, it is also required to shield US persons' identities "in such a way that a reasonable, well-informed person cannot identify the US person", and any information that is withheld because it identifies the person is to be held for no more than one year.
As part of sending raw intelligence to ISNU, there is the potential for communications to or from a US government official to be intercepted. While the NSA trusts Israel to the extent that the filtering of this information is left to the foreign nation, intelligence about government officials is held to a much higher standard than US persons.
"'Government officials' include officials of the Executive Branch (including the White House, Cabinet departments, and independent agencies); the House of Representatives and Senate (members and staff); and the US Federal Court system (including, but not limited to, the Supreme Court). 'Officials' include civilian and military members and employees performing the official business of these branches of government, and is independent of seniority or position."
Although the memo does lay out restrictions for which intelligence can be used, any disputes are meant to be resolved "through discussion" by all parties, and there is an understanding that no part will seek to enforce the terms of the agreement through any court or tribunal.
Enforcing the agreement would be difficult to do in any case, as the memo states upfront that it is "not intended to create any legally enforceable rights, and shall not be construed to be either an international agreement or a legally binding instrument according to international law".