Excerpts of the President's News Conference
There are quite a good many of the members of the conference that don't seem to be able to comprehend just what these conferences are held for. They are not in any sense interviews to be given out by the press, or statements. They simply furnish a background, so that if people who are writing for the press desire to write on a certain subject they may have the proper information with which to write their story. They ought not to be referred to as statements from the White House and there ought not to be any reference to the fact that there is a news-paper conference here. Constant practice of that kind by the men who write for the press hamper me very greatly in the help that I might give them. Every time I make a statement that is of any particular importance as news, those who undertake to write a story about it give it out as though it was a statement that I had made or an interview that I had given, so that I had to refrain from saying anything that might be reported along that line. So I suggest to you that you exercise more care about that and remember that these are not interviews and not statements from the White House, but simply information that I give to the press in order that it may intelligently write reports and comments about the subjects that I dwelt on.
Source: "The Talkative President: The Off-the-Record Press Conferences of Calvin Coolidge". eds. Howard H. Quint & Robert H. Ferrell. The University Massachusetts Press. 1964.
Calvin Coolidge, Excerpts of the President's News Conference Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/349233