Mr. Trump made his animus toward the news media clear during the presidential campaign, often expressing his disgust with coverage through Twitter or in diatribes at rallies. So if his campaign is any guide, Mr. Trump seems likely to enthusiastically embrace the aggressive crackdown on journalists and whistle-blowers that is an important yet little understood component of Mr. Obama's presidential legacy.

Criticism of Mr. Obama's stance on press freedom, government transparency and secrecy is hotly disputed by the White House, but many journalism groups say the record is clear. Over the past eight years, the administration has prosecuted nine cases involving whistle-blowers and leakers, compared with only three by all previous administrations combined. It has repeatedly used the Espionage Act, a relic of World War I-era red-baiting, not to prosecute spies but to go after government officials who talked to journalists.

Under Mr. Obama, the Justice Department and the F.B.I. have spied on reporters by monitoring their phone records, labeled one journalist an unindicted co-conspirator in a criminal case for simply doing reporting and issued subpoenas to other reporters to try to force them to reveal their sources and testify in criminal cases.