The letters, sent Thursday, are signed by Senate Judiciary Chairman Charles Grassley, ranking Democrat Dianne Feinstein, as well as Sens.
It's asking her to disclose any conversations with Hillary Clinton's campaign and the DNC about the FBIs investigation into the 2016 democratic presidential nominee's use of a private email server.
"It gave me a queasy feeling, " Comey testified, adding that the direction gave him the "impression" that the DOJ was aligning itself with the Clinton campaign.
The demand comes as the Judiciary Committee investigates the circumstances surrounding the dismissal of ex-FBI Director James Comey, in which the material may take on a new significance.
That false information prompted Comey to publicly declare in July that the investigation was over, but he criticized Clinton for "extremely careless" handling of classified info.More news: Amazon to Acquire Whole Foods for $13.7 Billion
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The alleged assurance was indicated in an email from then-Democratic National Committee Chair Debbie Wasserman Schultz to Leonard Benardo of the Open Society Foundations. The supposed Russian document said that in this email, Wasserman-Schultz claimed Lynch had assured a Clinton aide, Amanda Renteria, that she wouldn't let the FBI investigation into Clinton's emails go too far. The Post reported that the FBI considered the document bad intelligence and possibly even a fake sent to confuse the bureau. "Lynch would keep the Clinton investigation from going too far.' Chairman Grassley then requested a copy of the document from the Justice Department, which has failed to respond".
Notably, the letter does not ask Lynch to comment on Comey's testimony about treating the email investigation as a "matter".
Comey was allegedly concerned such communication would call into question the FBI's independence, and made a decision to announce the conclusion of the email investigation.
Lynch's surprise meeting with Bill Clinton on an airport tarmac last June drew instant scrutiny from Republicans.
The Washington Post story reported the document in question was viewed as "unreliable and possibly a fake" by people within the Federal Bureau of Investigation. By July 6, the Judiciary Committee requests copies of the documents and emails in question, and well as answers as to whether they existed in the first place and if the Federal Bureau of Investigation had previously tried to obtain them for the recipients.