(CNN) Five CIA employees who improperly accessed data belonging to the Senate Select Committee on Intelligence will not face disciplinary measures as they "acted reasonable under the complex and unprecedented circumstances in investigating a potential security breach in the highly classified shared computer network," according to an agency accountability board.

Chaired by former Sen. Evan Bayh, D-Indiana, alongside former Obama White House attorney Bob Bauer and three senior CIA officers, the board was convened in August 2014 by CIA Director John Brennan and tasked with investigating the misconduct and putting forward recommendations to ensure that "future instances of the miscommunication and confusion that led to this controversy" do not arise again.

The unusually public dispute between the Senate and the CIA over access to classified information began last year when the Senate Intelligence Committee began preparing a report that exposed the CIA's controversial detention and interrogation programs.

The CIA, in turn, accused Senate committee staffers of getting access to internal agency documents and improperly handling classified material, a charge the Justice Department determined was lacking evidence to warrant a further investigation.

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