It is however likely the IRS or FBI simply used a subpoena to get their information through a court and a judge, which is entirely in accordance with the law.
It is however likely the IRS or FBI simply used a subpoena to get their information through a court and a judge, which is entirely in accordance with the law.
So while its most likely that this went through a subpoena, it's absolutely not conspiratorial to suggest NSA involvement.
To quote: "In a Florida drug case he was handling, the prosecutor said, a DEA agent told him the investigation of a U.S. citizen began with a tip from an informant. When the prosecutor pressed for more information, he said, a DEA supervisor intervened and revealed that the tip had actually come through the SOD and from an NSA intercept."
Admittedly you only specified the IRS and FBI so perhaps you intentionally left out the DEA.
It doesn't seem that the NSA accepts anyone else's "authority". No authorized != doesn't happen. They can and do share information about regular crimes. See: "parallel construction". They provide this info secretly to local police so that they can create a clean chain of evidence without implicating the NSA.
I have an article here that claims 2700+ incidents from 2011 to 2012. One of which affected 3,000 Americans: "The most serious incidents included a violation of a court order and unauthorized use of data about more than 3,000 Americans and green-card holders. "[0] This is only an internal audit - the only cases I have read about are where this information is volunteered by the perpetrators or investigated after a suspicious victim, that knows about potential NSA involvement has come forward.
[0]http://www.washingtonpost.com/world/national-security/nsa-br...
If the NSA were authorised in another case or acquire the data unintentionally and happen upon incriminating evidence, they feel they are authorised to tip off the FBI - this is where parallel construction comes in.
Here's evidence that the IRS has received database information through SOD and the NSA, they have a manual for it:
http://www.reuters.com/article/2013/08/07/us-dea-irs-idUSBRE...