Donald Trump may be crowing that former FBI Director James Comey’s Thursday testimony to the Senate Intelligence Committee somehow vindicated him (it didn’t), but Comey laid a trail of breadcrumbs that congressional committees are now following. 

The House Intelligence Committee and the Senate Judiciary Committee have both come out with requests for Comey’s memos, with the latter addressed to Columbia Law School Professor Dan Richman and the former to Comey himself. Significantly, the House Intelligence Commitee announced that it has also requested any White House recordings of Comey's conversations with Trump. Specifically:

… the Committee wrote a letter to White House Counsel Don McGahn, requesting that he inform the Committee whether any White House recordings or memoranda of Comey’s conversations with President Trump now exist or have in the past. To the extent they exist now, the Committee’s letter asks that copies of such materials be produced to the Committee by June 23.

The White House has refused to answer repeated questions about the existence of such tapes and may well continue to do so, but it’ll be a different thing when it’s a congressional committee, rather than a reporter, asking.