Statement by the Press Secretary on Special Counsel Robert Mueller's Investigation
At the President's direction, the White House has been completely transparent with the Special Counsel's investigation. The Special Counsel received more than 1.4 million documents and hours and hours of interviews from White House officials, including more than 30 hours from former Counsel to the President, Don McGahn. The Democrats do not like the conclusion of the Mueller investigation – no collusion, no conspiracy, and no obstruction – and want a wasteful and unnecessary do-over.
The House Judiciary Committee has issued a subpoena to try and force Mr. McGahn to testify again. The Department of Justice has provided a legal opinion stating that, based on long-standing, bipartisan, and Constitutional precedent, the former Counsel to the President cannot be forced to give such testimony, and Mr. McGahn has been directed to act accordingly. This action has been taken in order to ensure that future Presidents can effectively execute the responsibilities of the Office of the Presidency.
Donald J. Trump, Statement by the Press Secretary on Special Counsel Robert Mueller's Investigation Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/334378