Comey testified two days later, on July 7, to a House committee. When members asked for a copy of the interview notes, he said "We will provide you with whatever we can under the law and under our policy."
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He also said the notes were classified Top Secret. An FBI official said Monday that since last month's hearing, FBI lawyers have been reviewing whether the notes can be turned over and whether any redactions were necessary.
The notes are not verbatim transcripts of the interview, which Comey said lasted three and a half hours. Under the FBI's long-standing policy, agents do not make audio or video recordings of their interviews. Instead, summaries of the interviews are written on FBI Form 302, and have come to be known as "302's."
An FBI policy paper explains that "the presence of recording equipment may interfere with and undermine the successful rapport-building interviewing technique which the FBI practices."
Two years ago, however, the Justice Department said FBI agents should begin recording interviews, but only involving "individuals in federal custody, after they have been arrested but before their initial appearance" in court.
That rule did not apply to the Clinton interview, which was voluntary. She was not in custody, nor had she been arrested.
Separately, two House Republicans sent a letter Monday to the U.S. attorney in Washington, listing statements she made in congressional hearings about the e-mail issue while she was secretary of state. Rep. Bob Goodlatte of Virginia, chairman of the Judiciary Committee, and Rep. Jason Chaffetz of Utah, chairman of the Oversight and Government Reform Committee, have urged the FBI to investigate whether the testimony amounted to perjury.