File, AP Photo/J. Scott Applewhite, Pool
In this Dec. 8, 2011, file photo, then-U.S. Secretary of State Hillary Rodham Clinton hands off her mobile phone after arriving to meet with Dutch Foreign Minister Uri Rosenthal at the Ministry of Foreign Affairs in The Hague, Netherlands. Clinton emailed her staff on an iPad as well as a BlackBerry while secretary of state, despite her explanation that she exclusively used a personal email address on a homebrew server so she could carry a single device, according to documents obtained by The Associated Press.

WASHINGTON — Two high-ranking Republican senators criticized Hillary Rodham Clinton's use of a personal email server, and one said Clinton likely violated federal law.

Texas Sen. John Cornyn, the No. 2 Republican in the Senate, said Thursday he wants the State Department's inspector general to investigate whether Clinton violated federal law or policy. Cornyn said in a letter to Inspector General Steve Linick that Clinton's use of a private server meant that her emails "remained beyond the reach of congressional investigations, the Freedom of Information Act and the (State) department's record-keeping practices for six years."

Iowa Sen. Charles Grassley, chairman of the Senate Judiciary Committee, said Clinton made a "great big mistake" by using a private email account for public business while she was secretary of state. Grassley told Newsmax TV this week that the use of a private server "probably violates the Freedom of Information Act, it probably violates national security legislation and it really hurts congressional oversight."

Clinton, a likely Democratic presidential candidate, used a private email account and server during her four-year tenure as secretary of state. She has refused a House committee's request to turn over her server for an independent review.

Her lawyer told a House committee investigating the deadly 2012 attacks in Benghazi, Libya, that all emails on the server were permanently deleted.

Clinton faces a Friday deadline to turn over the server, but lawyer David Kendall told the chairman of the Benghazi panel that doing so would be pointless, since "no emails ... reside on the server or on any backup systems associated with the server."

The State Department said last week that Secretary of State John Kerry has ordered an internal audit of the department's record-keeping in the aftermath of the revelations about Clinton's use of a private email account and server. Spokesman Jeff Rathke said the review was not specific to Clinton.

Cornyn, in his letter to the inspector general, said the inquiry should answer a series of questions about Clinton's actions, including whether her deletion of thousands of emails violated any federal civil or criminal law.

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