The National Security Agency has released an email sent by Edward Snowden to its Office of General Counsel last year, claiming it is the only email Snowden sent to supervisors before leaking documents on agency spying. In the email, Snowden raised questions about whether executive orders supersede federal laws. The release came after Snowden told NBC’s Brian Williams he had raised concerns through multiple channels.

Edward Snowden: “The NSA has records. They have copies of emails right now, to their Office of General Counsel, to their oversight and compliance folks, from me, raising concerns about the NSA’s interpretations of its legal authorities. Now, I had raised these complaints not just officially, in writing, through email, to these offices and these individuals, but to my supervisors, to my colleagues, in more than one office. … And the response, more or less, in bureaucratic language, was: 'You should stop asking questions.'”

Snowden told The Washington Post his correspondence extended far beyond the single email released by the NSA. He urged the White House to “require the NSA to ask my former colleagues, management, and the senior leadership team about whether I, at any time, raised concerns about the NSA’s improper and at times unconstitutional surveillance activities. It will not take long to receive an answer.”