As part of its immunity deals with Hillary Clinton’s lawyers, Cheryl Mills and Heather Samuelson, the Justice Department agreed to destroy laptops the attorneys turned over to federal investigators and to limit searches of the devices to documents created before Jan. 31, 2015.

The perplexing “side agreements” are revealed in a letter that Virginia Rep. Bob Goodlatte sent to Attorney General Loretta Lynch on Monday.

Investigators with the House Judiciary Committee, which Goodlatte chairs, were able to review the DOJ’s agreements with Mills and Samuelson, who worked as aides to Clinton at the State Department before taking jobs as her lawyers.

“Please explain why DOJ agreed to limit their search of the Mills and Samuelson laptops to a date no later than January 31, 2015,” Goodlatte writes in the letter, which was first reported by Fox News and obtained by The Daily Caller.

He goes on to assert that the side agreements to limit the search, which were signed on June 10, meant that investigators gave up “any opportunity to find evidence related to the destruction of evidence or obstruction of justice related to Secretary Clinton’s unauthorized use of a private email server during her tenure as Secretary of State.”

“Why was this time limit necessary when Ms. Mills and Ms. Samuelson were granted immunity for any potential destruction of evidence charges?” he asks.

It was revealed last month that the DOJ granted Mills and Samuelson immunity for any information recovered from their laptops. In a House Judiciary Committee hearing last week, FBI director James Comey said that he agreed to grant immunity because he expected that a request for lawyers’ laptops would lead to a protracted legal battle.

He did not mention the side agreements or that Mills’ and Samuelson’s laptops were destroyed.

The agreement to forego searches after Jan. 31, 2015, prevented the FBI from investigating a key period of the Clinton email fiasco.

On March 31, 2015, the computer technician who handled Clinton’s server used a software program called BleachBit to delete backups of Clinton’s emails. Just after deleting the emails, the technician, Paul Combetta, took part in a conference call with Mills and another Clinton lawyer, David Kendall. Combetta was ordered by his attorney to not answer the FBI’s questions about what was said in that conference call.

The mystery surrounding that conference call has led to speculation that Mills, Kendall and Combetta (who also received DOJ immunity) discussed the deletion.

Comey said last week that investigators found no evidence that Mills ordered Combetta to delete the emails. But the revelation of the side agreement raises the question of whether Comey was asserting that no evidence obtained before Jan. 31, 2015 pointed to obstruction of justice.

“Like many things about this case, these new materials raise more questions than answers,” Goodlatte wrote to Lynch.

In the letter, the Republican also asks whether a grand jury was convened as part of the Clinton email probe.

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