Jamie Gorelick wrote an op-ed piece in Sunday's Washington Post explaining the intelligence sharing wall and her role in it. Her op-ed is testimony because it contains "facts". Unlike AG John Ashcroft's revelation about Gorelick's role in inventing the intel-sharing-prevention wall, Gorelick's op-ed is NOT sworn and NOT delivered under penalty of perjury. It is also entirely disingenuous, as Andrew McCarthy shows here. McCarthy links to Gorelick's op-ed in his essay.
Note also the Volokh Conspiracy has some thoughts on Gorelick here.