United States Army Counterintelligence Command (ACIC) is the component of United States Army's Military Intelligence Corps that directs counterintelligence (CI) activities to detect, identify, assess, counter, exploit and/or neutralize adversarial, foreign intelligence services, terrorist organizations, and insider threats to the United States Army and United States Department of Defense.United States Army Regulation 381-20, The Army Counterintelligence Program, May 25, 2010
Overview ACI Command or "ACIC" is the one organization in the Army that has a sole mission of counterintelligence although it is not yet specifically designated by the Office of the Under Secretary of Defense for Intelligence and Security, as a "Military Department CI Organization" or "MDCO" (likely due to the applicable DoD Instruction not receiving a revision since ACIC stood up). The MDCO for the Army is currently defined more broadly as simply Army Counterintelligence (ACI), despite ACIC having the bulk of the CI mission and being the only "full-spectrum" CI entity within the Department of the Army.DOD INSTRUCTION O-5240.10, COUNTERINTELLIGENCE (CI) IN THE DOD COMPONENTS, April 27, 2020 The Navy and Air Force have specific organizations designated as DoD MDCO's: Department of the Air Force Office of Special Investigations (OSI) and the Naval Criminal Investigative Service (NCIS). Special Agents of ACI have full law enforcement authority within its military jurisdiction associated with its counterintelligence mission which includes conducting national security criminal investigations in conjunction with other CI activities. Other CI entities within the DoD not recognized as MDCOs, such as Marine Corps Counterintelligence and the Defense Counterintelligence and Security Agency (DCSA) have no direct criminal investigative mission and therefore are designated only as "intelligence" or "security" organizations; although they may assist in such investigations in a non-law enforcement capacity as authorized by Executive Order 12333 and applicable regulations.
ACI Special Agents are U.S. Army personnel, either military or civilian, who are trained and appointed to conduct CI investigations and operations for the U.S. Army and DoD. To enable their law enforcement role federal law enforcement, they are issued badges and credentials and have apprehension authority under the Uniform Code of Military Justice with regards to U.S. Army Service Members and certain civilians in overseas environments. On 23 December 2024 the Fiscal Year (FY) 2025 National Defense Authorization Act (NDAA) was signed into law, becoming Public Law 118-159. The FY25 NDAA authorized a change to 10 USC 7377 which expands civilian ACIC Special Agents' existing Federal Law Enforcement Authority and provides statutory authority under U.S. Code to make/execute arrests and serve warrants pertaining to civilian or service member investigative subjects.
ACI Special Agents specialize in the investigation of national security crimes committed by Army service members, civilians, contractors, dependents and other DoD personnel. These crimes include treason, spying, espionage, sedition, subversion, sabotage or assassination directed by foreign governments/actors, and support to (and acts of) international terrorism. ACI Special Agents do not have jurisdiction over general criminal matters, which are investigated by the United States Army Criminal Investigation Division (CID).United States Army Techniques Publication 2-22.2-1, Counterintelligence Investigations, Counterintelligence Investigative JurisdictionUnited States Army Regulation 195-2, Criminal Investigation Activities, June 9, 2014 However, due to the new statutory authorities granted to civilian ACIC agents, should a crime outside of national security crimes be connected to a CI investigation, ACIC Agents now have authority to obtain warrants and conduct arrests for those crimes under the umbrella of the CI investigations (within the scope outlined in their agency policies and regulations). In other branches of the U.S. military, both general criminal and counterintelligence investigations are performed by the same entity, as seen with AFOSI and NCIS who are also identified as "Defense Criminal Investigative Organizations."DOD INSTRUCTION 5505.16, INVESTIGATIONS BY DOD COMPONENTS, June 23, 2017 The Army continues to keep these investigative activities separate via ACI and CID, although parallel and joint investigations happen periodically between these two U.S. Army agencies.
Most operational ACI Special Agents today work under the auspices of the United States Army Intelligence and Security Command (INSCOM) with ACIC responsible for CI activities and operating Regions, Field Offices, and Resident Agencies world-wide in addition to managing all investigative activity through the Army CI Coordinating Authority (ACICA). Additionally, outside the continental U.S., other units with ACI agents currently provide additional theater-specific CI support to U.S. Army elements, such as the 500th Military Intelligence Brigade covering INDOPACOM areas such as Hawaii and Japan, the 501st Military Intelligence Brigade covering South Korea, the 66th Military Intelligence Brigade covering EUCOM, 470th Military Intelligence Brigade covering South America, and the 513th Military Intelligence Brigade covering the greater Middle East. The 650th Military Intelligence Group covers NATO missions in applicable countries under Allied Command Counterintelligence or "ACCI." Other U.S. Army elements also have ACI Special Agents assigned to provide direct support to units/organizations, such as those found within the various elements of Special Operations.
History Prior to World War I, the U.S. military had no standing counterintelligence services, requiring the use of other elements to conduct counterintelligence activities, such as founding father John Jay's Committee for Detecting and Defeating Conspiracies and the Culper Spy Ring during the American Revolution, and by Allan Pinkerton and his private detectives during the U.S. Civil War.
ACI was formed as a standing CI service in 1917 during World War I, as the Corps of Intelligence Police (CIP) under the newly created Military Intelligence Division commanded by Colonel Ralph Van Deman following a request to the Chief of Staff of the Army by the American Expeditionary Forces (AEF) G-2, Major Dennis Nolan.
Nolan requested 50 men with police/investigative experience to assist British and French counter-espionage efforts at French ports and on the front lines. Both requests were approved the following month and the CIP became the first official recognition of the counterintelligence discipline in the U.S. Army. The first 50 CIP special agents arrived in France in November 1917. Two months later, the AEF received authorization to recruit another 700 agents from units already overseas. However, by the armistice in November 1918, the CIP had only reached a strength of 418 agents.
CIP agents provided security for ports in France, England and Scotland; 400 miles of frontier along the borders with Spain and Italy; 31 supply depots; and seven leave centers. They worked undercover as laborers and interpreters to detect enemy agents circulating among U.S. troops. They also warned Soldiers about the consequences of "loose talk" and investigated suspicious behavior or cases of possible sabotage. CIP agents investigated thousands of cases and neutralized hundreds of suspected enemy agents through conviction, internment, or expulsion from the war zone. Additionally, some CIP agents worked "Special Projects" in the Counter Espionage Section of the AEF G-2 while also providing security for traveling VIPs and, at times, served as Gen. John Pershing's bodyguards.
The secret nature of much of the CIP's work meant that their successes often went unrecognized. Rank disparity often also became an issue when agents interviewed senior officers or interacted with Allied counterintelligence personnel. Finally, the word "police" in the organization's title led to CIP investigations of more criminal activities, much to the consternation of the Military Police.
Despite these problems, CIP agents were exceedingly proud of their service. According to their official history, "World War I experiences taught most CIP agents that it was hard, unglamorous and painstaking work that earned for the CIP a permanent and honored place in all the future wartime plans of the United States Army." This, however, did not protect CIP from post-war reductions along with the rest of the US Army.
At the outbreak of World War II, the CIP expanded drastically and was rebranded as the Counter Intelligence Corps (CIC) which it remained during the initial part of the Cold War. In 1961, the CIC was disbanded, following repeated attempts by various leaders to merge CI with other intelligence disciplines that all resulted in degraded capabilities. Following further intelligence reforms related to violations of civil liberties across the U.S. intelligence community, Army CI agents were eventually dispersed and placed under the control of different military intelligence organizations that followed into the present day under INSCOM. What followed was several decades of a drastically less capable ACI, and arguably more aggressive foreign threats targeting the U.S. Army and DoD.
In more recent history while conducting operations in tactical environments, ACI Agents were often misused as Human Intelligence (HUMINT) collectors during a period where HUMINT authorities were transferred to the DIA in the 1990s. However, after organic HUMINT collectors got their authorities back, ACI Agents were still used in this fashion by commanders well into the Global War on Terrorism, partnering them with HUMINT in tactical environments in what were called Tactical Human Intelligence Teams (THTs), later referred to as Human Intelligence Collection Teams (HCTs). (Note: the US Marine Corps equivalent is referred to as Human Intelligence Exploitation Teams or HETs.) THTs were designed to not only collect and report HUMINT but to also exploit that intelligence information by acting on it, although agents partnering with HUMINT in this fashion is not always viewed as ideal with many CI experts concluding this as a less effective way to counter adversarial intelligence and terrorist networks.
In response to the rise in foreign adversaries (both foreign intelligence and terrorism) targeting the U.S. Army, ACI Command (ACIC) was formed in 2021 delegating all Secretary of the Army "CI and national security criminal investigative authorities" under that command. ACIC once again brings a unified ACI under a single flattened structure to quickly handle foreign threats to the U.S. Army. Today, ACIC manages investigations worldwide through supported Regions, Field Offices, and Resident Agencies.
Special Agent duties ACI Special Agent duties include the investigation of national security crimes, conducting counterintelligence operations, processing intelligence evidence, conducting both surveillance and counter-surveillance activities, protecting sensitive technologies, preparing and distributing reports, conducting source/informant operations, debriefing personnel for counterintelligence collections, and supporting counter-terrorism operations.