You’re thinking of Reagan testifying before Congress about Iran Contra.
It worked for Karl Rove and Dick Cheney when they talked about vote manipulation in 2004.
It was also the only way Spiro Agnew got through his corruption hearing in front of Congress while Nixon tried to do the same for Watergate until the taped conversations were released.
It’s a time tested conservative play when confronted by a request to tell the truth: don’t lie but deny the allegations. Weirdly, I can’t find any time a democrat, Hilary or otherwise, repeated “I don’t recall” for their entire testimony. It just seems to be a conservative play.