President Trump listens during a news conference on April 12. (Jabin Botsford/The Washington Post)

President Trump’s Friday morning tweetstorm about former FBI director James B. Comey has led to speculation that the Trump administration has taken a page from Richard Nixon’s playbook by surreptitiously recording conversations inside the White House.

As it happens, Nixon wasn’t the only president to record his conversations. Six American presidents — from Franklin Delano Roosevelt to Nixon — taped at least some of their conversations. President Ronald Reagan and his successors had several meetings videotaped.

There are a number of reasons presidents might want to have their conversations recorded. Sometimes these reasons overlap.

First, they can help protect the president from later conflicts about who said what — and when. In the eyes of Nixon’s capable chief of staff, H.R. Haldeman, the “primary intent” of taping conversations was to protect Nixon, like earlier presidents who had taped their conversations, “from the convenient lapses of memory of his associates.” The purpose of the tapes “was not,” Haldeman argued, “to provide tapes for historians to peruse, but for the president’s use alone — for reference when visitors … made statements that conflicted with their private talks with the president.” Trump’s tweet subtly echoes Haldeman’s explanation.

Second, they can later be monetized. Keen observer that he was, Haldeman also noted “a secondary benefit” of the tapes, that of providing the president “with valuable reference material for his own use.” Nixon’s predecessor, Lyndon Johnson, had likewise found his own recorded telephone conversations useful when he wrote his memoir, “The Vantage Point.” According to Nixon, Johnson:

had a taping system for his office phone, his bedroom phone, the phone at Camp David, the phone at his ranch in Johnson City, and the phone at his office in Austin. In addition to the phone equipment, he had room microphones placed in the Cabinet Room and in the private office next to the Oval Office. At one point there was also a recording device that could pick up conversations in the room outside the Oval Office where Johnson’s visitors would wait before being ushered in to see him. The Johnson system was operated manually, which permitted him to decide which conversations to record. … Johnson thought that my decision to remove his taping system was a mistake; he felt his tapes were invaluable in writing his memoirs.

Thus, recorded conversations can provide the raw material for profitable post-presidency memoirs.

Finally, taped conversations may be more immediately useful in running the White House, which is a large and complex organization. Presidents no doubt have a sense that they are making history, so having a record of phone conversations or meetings is also useful for conducting day-to-day affairs.

Nixon was pretty explicit that the secrecy of the taping system was paramount. In the first conversation captured on tape, for example, Nixon described the reason behind his decision to tape to Alexander Butterfield, the aide who revealed the existence of the taping system to the congressional committee investigating Watergate in July 1973. Echoing the rationale he would express years later in his memoirs, Nixon told Butterfield, “You see, the purpose of this is to have the whole thing on the file for professional reasons.” Butterfield told the president that he had gone over the potential use of the tapes for note-taking with Haldeman, and noted that the system was an office secret, because “there are only five people who know about it, outside of Haldeman, then you and me.”

Furthermore, Nixon did not want a verbatim transcript of his meetings or phone conversation. “Mum’s the whole word. I will not be transcribed,” Nixon told Butterfield and Haldeman. If for some reason material from the tapes was needed, perhaps, as Nixon noted, “maybe we want to put out something that’s positive, maybe we need something just to be sure that we can correct the record.” Haldeman noted that, rather than mention the existence of a taping system, the correction would be “on the basis of ‘Butterfield’s notes’ or ‘the president’s notes’ or ‘my notes.’ ”

Nixon and Haldeman separately discussed uses of the secret taping system to review tapes related to the disclosure that Undersecretary of the Interior Fred Russell had been fired. In one conversation, Nixon suggested to Haldeman that he use the tape regarding instructions on how Russell’s resignation-cum-firing should be portrayed to the media. Haldeman was clearly enthusiastic and advised the president, “Let’s use the recording,” but suggested it be done “on the basis of your notes.” Nixon again expressed his desire to avoid tape transcription: “I don’t want you to transcribe those unless it’s important. See?”

Confirming what he said in his memoirs years later, in another taped conversation Nixon lamented the problems of having a note taker in meetings to Haldeman: “It just doesn’t work to have somebody be in here every minute.” The sheer volume of memoranda of conversation (memcons), telephone conversation (telcons) transcripts, meeting notes, diaries, and memoranda for the record, and millions of pages of textual documents produced by the administration attest to Nixon’s desire for thorough, reliable and accurate record — but also a record that would flatter the administration.

Thus, Nixon had a variety of reasons for recording his conversations, including maintaining political leverage, bureaucratic record-keeping, the monetary value of the recordings, the ability to use records to put a positive spin on news, and also of vanity.

We don’t know yet whether Trump has a taping system in his White House. If he does, it is plausible that he might be motivated by some of the same reasons as Nixon was — leverage, ego and spin. It may also be that tapes have unanticipated consequences for Trump. Nixon’s concern with keeping the tapes secret probably was because he anticipated that public knowledge of them could mean that they were used as a public weapon against him. If Trump has tapes, he may end up similarly discomforted.

This article draws on Richard A. Moss and Luke Nichter, “Play, Pause, Stop, Record: Why Presidents Taped—The Case of Richard Nixon,” http://nixontapes.org/origin.html. Moss is an associate research professor at the U.S. Naval War College and the author of “Nixon’s Back Channel To Moscow: Confidential Diplomacy and Detente,” published by the University Press of Kentucky in January 2017.