Story highlights The announcement comes after criticism of the Justice Department's handling of the investigation

The email controversy a major issue on the 2016 campaign trail

Washington (CNN) The Justice Department's internal watchdog announced Thursday it has launched a probe into the department and the FBI's handling of the investigation into Hillary Clinton's private email server.

The announcement, which was expected, comes after criticism of the Justice Department's handling of the investigation, particularly on how the public was notified about the controversy, which was a major issue on the 2016 campaign trail.

It will likely mean questions over the role of FBI Director James Comey in the fading days of the election, which Democrats believe helped cost them the presidency, will linger on long into the administration of Donald Trump.

Justice Department Inspector General Michael E. Horowitz said the decision to initiate a review was prompted by requests from numerous members of Congress and public inquiries.

Horowitz's office said the review will examine several allegations, including that DOJ or FBI policies were not followed when Comey publicly stated last July that his bureau would not pursue criminal charges against Clinton; that DOJ and FBI employees improperly disclosed non-public information; and that the timing of the FBI's release of certain Freedom of Information Act requests right before the election was improper.

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