Federal prosecutors in Washington recently began investigating the 2017 leak of classified information to reporters at The New York Times and The Washington Post, and appear to be focusing on whether former FBI Director James Comey was involved, people with knowledge of the matter told the Times.
The Post and Times articles both mentioned a Russian government document that was obtained by Dutch intelligence officials and passed along to the FBI. The existence of the document and its collection method were both highly classified secrets. The document, which appeared to be part of a Russian disinformation campaign, played a role in Comey's decision to announce in July 2016 that the FBI did not plan on recommending Hillary Clinton face charges for her use of a private email server while secretary of state.
Typically, leaks of classified information are investigated as soon as they appear in the media, not several years later. It's unclear if there is a grand jury, the number of witnesses interviewed, or what prompted the investigation, although the timing raises the question of whether it is motivated by politics, the Times notes. Federal prosecutors in New York already investigated Comey after he asked his personal lawyer and friend Daniel Richman to give a Times reporter contents of the memo he wrote about his interactions with Trump. It was retroactively determined that the memo contained classified information, but prosecutors declined to charge Comey with a crime.