John Charles Demers (born September 21, 1971) is an Italian-born American lawyer who served as United States Assistant Attorney General for the National Security Division (NSD) from 2018 to 2021.

[2] During his tenure in the NSD, he was selected by Attorney General Jeff Sessions to lead the China Initiative and oversaw counterespionage operations in foreign intelligence.

[4] Demers returned to work at Boeing afterward, where he previously had been a vice president and general counsel leading the company's international defense, space, and security affairs.

[9][6] After attaining a Watson Fellowship to study in Italy, Demers became a research assistant for the National Center on Addiction and Substance Abuse at Columbia University, then enrolled in Harvard Law School in August 1996.

[3] He clerked at the United States Attorney's Office for the District of Massachusetts in 1997 and was a summer associate at the law firm of Simpson Thacher & Bartlett in 1998.

[15][16] Demers was brought to work at the Boeing Company in Arlington, Virginia, by retired judge J. Michael Luttig, formerly of the United States Court of Appeals for the Fourth Circuit.

"[27] The program aimed to counter Chinese espionage and intelligence activities in the U.S.[28][29] Attorney General Jeff Sessions selected Demers to lead the initiative.

[3] These initiatives were continued by the Department of Justice under Demer's nominated successor, Matthew Olsen, until he would later announce its termination in 2022 amid criticism for racial profiling.

[30] On January 20, 2021, acting attorney general Jeffrey A. Rosen resigned, and it became expected that Monty Wilkinson would serve in the position until Biden's nominee, Merrick Garland, could assume the office.

Before Biden signed an executive order naming Wilkinson to succeed Rosen, Demers served as acting attorney general for a few hours that day in the meantime.

[33] He was asked by acting United States Deputy Attorney General John P. Carlin to remain in the department in order to provide continuity as it would have been months before a new leader for the National Security Division could be confirmed.

Though his departure was planned months earlier, it came amid controversy regarding leaks of classified information that were being investigated, during which prosecutors seized records from The New York Times, The Washington Post, and CNN.

[3] Senate Majority Leader Chuck Schumer sought to subpoena Demers and called on him to testify before Congress along with Jeff Sessions and William Barr.

[42] On January 25, 2023, the National Security Institute of the Antonin Scalia Law School at George Mason University announced that Demers would be a member of its advisory board.