But despite months of investigation, prosecutors have been unable to bring charges against the man, who is a former CIA employee being held in a Manhattan jail on unrelated charges.

Joshua Adam Schulte, who worked for a CIA group that designs computer code to spy on foreign adversaries, is believed to have provided the agency’s top-secret information to WikiLeaks, federal prosecutors acknowledged in a hearing in January. The anti-secrecy group published the code under the label “Vault 7” in March 2017. It was one of the most significant and potentially damaging leaks in the CIA’s history, exposing secret cyberweapons and spying techniques that might be used against the United States, according to current and former intelligence officials.