Officials at both the CIA and on Capitol Hill said his departure was unrelated to politics or anything he had investigated.
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CIA inspector general David Buckley, who investigated a dispute between the agency and Congress over the handling of records of the CIA’s detention and interrogation activities, is resigning effective Jan. 31, the CIA said on Monday.

The agency said in a statement that Buckley, who has served as the agency’s internal watchdog for more than four years, was leaving the agency to “pursue an opportunity in the private sector.”