The Senate is investigating whether former Attorney General Loretta Lynch interfered in the Clinton email investigation
The senators - Republicans Lindsay Graham and Chuck Grassley and Democrats Dianne Feinstein and Sheldon Whitehouse - were prompted in part by former FBI Director James Comey's June Senate testimony, in which he said that he was "confused" and "concerned" by Lynch's treatment of the investigation.
Comey said that Lynch's widely criticized meeting on an airport tarmac in Pheonix with former Bill Clinton in June 2016, as well as her request that he call the investigation a "matter," convinced him that he had to take action to prove the Clinton investigation was being fairly conducted.
"In an ultimately conclusive way, that was the thing that capped it for me," Comey said. "I had to do something separately to protect the credibility of the investigation, which meant both the FBI and the Justice Department."
Although both Lynch and Bill Clinton have denied they discussed the email probe during their private meeting and instead made small talk about golf and Clinton's grandchildren, both received intense blowback over creating the appearance of impropriety during an ongoing investigation.
That backlash ultimately led Lynch to say she would accept the findings of the FBI and career prosecutors who were investigating Clinton's use of a private email server while she was secretary of state.
Comey added in his June 8 testimony that Lynch's alleged inference gave him a "queasy feeling."
On June 11, Feinstein told CNN that while she could not say whether Lynch asked Comey to provide "semantic cover" to the Clinton campaign, she "would feel queasy, too" if she had been in Comey's shoes.
In a Friday afternoon statement, Graham's spokesperson wrote that the senators were also prompted by two reports: one that a Democratic operative had assured colleagues that Lynch would prevent the email investigation from "going too far," and another report that then-chair of the Democratic National Committee Debbie Wasserman Schultz told Leonard Benardo of the Open Society Foundations that Lynch had told Clinton campaign staffer Amanda Renteria as much.
The senators sent letters to Benardo, OSF General Counsel Gail Scovell, Renteria, and Lynch asking for more information.
"Graham and the Senators seek details about the reported communication, copies of any related documents and whether the FBI contacted them to investigate the alleged communication," Graham's spokesperson wrote in a statement on Friday afternoon.
Michelle Mark contributed reporting.