The Pentagon's mass polygraph testing of Joint Staff members is justified

From the articleTop military officials faced polygraphs over leaks of sensitive information on weapons stockpiles, sources sayAlso in Pentagon polygraphs dozens of US military staff over media leaks, Top US military officials face lie-detectors in hunt over classified stockpiles leak: Reports, Pentagon subjects 50 members of the joint staff to polygraph tests in expanded leak hunt, ‘Treasonous’: Pentagon forces staff to take polygraphs in hunt for leaks to journalists