Justin Cooper, who helped set up Hillary Clinton’s private home email system, testified Tuesday before the House Oversight Committee and admitted that he had no national security clearance during the time he had access to all of Hillary Clinton’s emails while she was Secretary of State.

Cooper, who was a former aide to President Bill Clinton, said “I did not have a security clearance” while setting up and servicing Hillary Clinton’s private email server, laptops, and mobile devices.

Cooper’s confession came during day two of the Rep. Jason Chaffetz-led Oversight and Government Reform Committee hearing. Chaffetz issued a subpoena to top FBI official Jason Herring on Monday for every document related to the bureau’s investigation into Hillary Clinton’s use of a private email server while she was Secretary of State.

During Tuesday’s hearing, two employees of Colorado tech company Platte River Networks — the firm that maintained Clinton’s private home server — repeatedly invoked their Fifth Amendment rights against self-incrimination.

“Who told you to delete the emails?” Rep. Chaffetz asked Paul Combetta of Platte River Networks about Clinton’s email server.

“On the advice of counsel, I respectfully decline to answer and assert my Fifth Amendment privilege,” Combetta said. Combetta was reportedly granted immunity by the Department of Justice during its investigation of Clinton’s mishandling of classified emails while at State.

Platte River Networks employee Bill Thornton also pleaded the Fifth Amendment.

Another witness, former State Department technology adviser Bryan Magliano, failed to show up to the hearing.

“When you are served a subpoena for the United States Congress, it is not optional,” said Rep. Chaffetz.

Cooper, who said he was being paid by the Clintons and the Clinton Foundation while setting up and servicing Clinton’s personal server, was also named in a heavily redacted 58-page FBI report for using a hammer to destroy then-Secretary Clinton’s old Blackberry devices.

Cooper told the committee that cyber attackers made several “brute force” hacking attempts against Hillary Clinton’s email server, and added that he “had developed systems” to “tamp down” the cyber attacks.

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