Updated February 1, 2024
Defense Primer: U.S. Policy on Lethal Autonomous
Weapon Systems
Lethal autonomous weapon systems (LAWS) are a special
that “only engage individual targets or specific target
class of weapon systems that use sensor suites and
groups that have been selected by a human operator.” Semi-
computer algorithms to independently identify a target and
autonomous weapons include so-called “fire and forget”
employ an onboard weapon system to engage and destroy
weapons, such as certain types of guided missiles, that
the target without manual human control of the system.
deliver effects to human-identified targets using
Although these systems are not yet in widespread
autonomous functions.
development, it is believed they would enable military
The directive does not apply to autonomous or semi-
operations in communications-degraded or -denied
autonomous cyberspace capabilities; unarmed platforms;
environments in which traditional systems may not be able
unguided munitions; munitions manually guided by the
to operate.
operator (e.g., laser- or wire-guided munitions); mines;
Contrary to a number of news reports, U.S. policy does not
unexploded explosive ordnance; or autonomous or semi-
prohibit the development or employment of LAWS.
autonomous systems that are not weapon systems, nor
Although the United States is not known to currently have
subject them to its guidelines.
LAWS in its inventory, some senior military and defense
Role of human operator. DODD 3000.09 requires that all
leaders have stated that the United States may be compelled
systems, including LAWS, be designed to “allow
to develop LAWS in the future if U.S. competitors choose
commanders and operators to exercise appropriate levels of
to do so. At the same time, a growing number of states and
human judgment over the use of force.” As noted in an
nongovernmental organizations are appealing to the
August 2018 U.S. government white paper, “‘appropriate’
international community for regulation of or a ban on
is a flexible term that reflects the fact that there is not a
LAWS due to ethical concerns.
fixed, one-size-fits-all level of human judgment that should
Developments in both autonomous weapons technology and
be applied to every context. What is ‘appropriate’ can differ
international discussions of LAWS could hold implications
across weapon systems, domains of warfare, types of
for congressional oversight, defense investments, military
warfare, operational contexts, and even across different
concepts of operations, treaty-making, and the future of
functions in a weapon system.”
war.
Furthermore, “human judgment over the use of force” does
U.S. Policy
not require manual human “control” of the weapon system,
Then-Deputy Secretary of Defense Ashton Carter issued
as is often reported, but rather broader human involvement
DOD’s policy on autonomy in weapons systems,
in decisions about how, when, where, and why the weapon
Department of Defense Directive (DODD) 3000.09 (the
will be employed. This includes a human determination that
directive), in November 2012. DOD has since updated the
the weapon will be used “with appropriate care and in
directive—most recently in January 2023.
accordance with the law of war, applicable treaties, weapon
system safety rules, and applicable rules of engagement.”
Definitions. There is no agreed definition of lethal
To aid this determination, DODD 3000.09 requires that
autonomous weapon systems that is used in international
“[a]dequate training, [tactics, techniques, and procedures],
fora. However, DODD 3000.09 provides definitions for
and doctrine are available, periodically reviewed, and used
different categories of autonomous weapon systems for the
by system operators and commanders to understand the
purposes of the U.S. military. These definitions are
functioning, capabilities, and limitations of the system’s
principally grounded in the role of the human operator with
autonomy in realistic operational conditions.” The directive
regard to target selection and engagement decisions, rather
also requires that the weapon’s human-machine interface be
than in the technological sophistication of the weapon
“readily understandable to trained operators” so they can
system.
make informed decisions regarding the weapon’s use.
DODD 3000.09 defines LAWS as “weapon system[s] that,
Weapons review process. DODD 3000.09 requires that the
once activated, can select and engage targets without
further intervention by a human operator.” This concept of
software and hardware of covered semi-autonomous and
autonomous weapon systems, be tested and evaluated to
autonomy is also known as “human out of the loop” or “full
autonomy.” The directive contrasts LAWS with human
ensure they
-
supervised, or “human on the loop,” autonomous weapon
systems, in which operators have the ability to monitor and
Function as anticipated in realistic operational
halt a weapon’s target engagement. Another category is
environments against adaptive adversaries taking
semi-autonomous, or “human in the loop,” weapon systems
realistic and practicable countermeasures, [and]
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Defense Primer: U.S. Policy on Lethal Autonomous Weapon Systems
complete engagements within a timeframe and
distinction requirements of the law of war. The U.S.
geographic area, as well as other relevant
government does not currently support a ban on LAWS and
environmental
and
operational
constraints,
has addressed ethical concerns about the systems in a
consistent with commander and operator intentions.
March 2018 white paper, “Humanitarian Benefits of
If unable to do so, the systems will terminate the
Emerging Technologies in the Area of Lethal Autonomous
engagement or obtain additional operator input
Weapons.” The paper notes that “automated target
before continuing the engagement.
identification, tracking, selection, and engagement
functions can allow weapons to strike military objectives
Systems must also be “sufficiently robust to minimize the
more accurately and with less risk of collateral damage” or
probability and consequences of failures.” Any changes to
civilian casualties.
the system’s operating state—for example, due to machine
learning—would require the system to go through testing
Although the U.N. CCW is a consensus-based forum, the
and evaluation again to ensure that it has retained its safety
outcome of its discussions could hold implications for U.S.
features and ability to operate as intended. The directive
policy on lethal autonomous weapons.
also notes that “the use of AI capabilities in autonomous or
Potential Questions for Congress
semi-autonomous systems will be consistent with the DOD
AI Ethical Principles.”
•

What is the status of U.S. competitors’ development of
LAWS? Is the United States adequately investing in
Senior-level review. In addition to the standard weapons
counter-autonomy capabilities?
review process, a secondary senior-level review is required
• To what extent, if at all, should the United States initiate
for covered autonomous and semi-autonomous systems.
or accelerate its own development of LAWS?
This review requires the Under Secretary of Defense for
•
Policy (USD[P]), the Vice Chairman of the Joint Chiefs of
How should the United States balance LAWS research
Staff (VCJCS), and the Under Secretary of Defense for
and development with ethical considerations? What, if
Research and Engineering (USD[R&E]) to approve the
any, restrictions should there be on DOD’s development
system before formal development. USD(P), VCJCS, and
or employment of LAWS?
the Under Secretary of Defense for Acquisition and
• If the United States chooses to develop LAWS, are
Sustainment (USD[A&S]) must then approve the system
current weapons review processes and legal standards
before fielding. In the event of “urgent military need,” this
for their employment in conflict sufficient?
senior-level review may be waived by the Deputy Secretary
• What role should the United States play in U.N. CCW
of Defense. DODD 3000.09 additionally establishes the
discussions of LAWS? Should the United States support
Autonomous Weapon System Working Group—composed
the status quo, propose a political declaration, or
of representatives of USD(P); USD(R&E); USD(A&S);
advocate regulation of or a ban on LAWS?
DOD General Counsel; the Chief Digital and AI Officer;
the Director, Operational Test and Evaluation; and the
CRS Products
Chairman of the Joint Chiefs of Staff—to support and
advise the senior-level review process.
CRS In Focus IF11294, International Discussions Concerning
Lethal Autonomous Weapon Systems, by Kelley M. Sayler.
Congressional notification. Per Section 251 of the FY2024
CRS Report R45178, Artificial Intelligence and National Security,
NDAA (P.L. 118-31), the Secretary of Defense is to notify
by Kelley M. Sayler.
the defense committees of any changes to DODD 3000.09
within 30 days. The Secretary is directed to provide a
description of the modification and an explanation of the
Other Resources
reasons for the modification.
Department of Defense Directive 3000.09, “Autonomy in
Weapon Systems,” Updated January 25, 2023,
International Discussions of LAWS
https://www.esd.whs.mil/portals/54/documents/dd/issuances/d
Since 2014, the United States has participated in
odd/300009p.pdf.
international discussions of LAWS, sometimes colloquially
U.S. Government, “Humanitarian Benefits of Emerging
referred to as “killer robots,” under the auspices of the
Technologies in the Area of Lethal Autonomous Weapons,”
United Nations Convention on Certain Conventional
March 28, 2018.
Weapons (U.N. CCW). In 2017, these discussions
transitioned from an informal “meeting of experts” to a
U.S. Government, “Human-Machine Interaction in the
formal “Group of Governmental Experts” (GGE) tasked
Development, Deployment and Use of Emerging Technologies
with examining the technological, military, ethical, and
in the Area of Lethal Autonomous Weapons Systems,” August
legal dimensions of LAWS. In 2018 and 2019, the GGE has
28, 2018.
considered proposals by states parties to issue political
United Nations Office at Geneva, “Background on Lethal
declarations about LAWS, as well as proposals to regulate
Autonomous Weapons Systems in the CCW.”
them.

In addition, approximately 30 countries and 165
nongovernmental organizations have called for a
Kelley M. Sayler, Analyst in Advanced Technology and
preemptive ban on LAWS due to ethical concerns,
Global Security
including concerns about operational risk, accountability
for use, and compliance with the proportionality and
IF11150
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Defense Primer: U.S. Policy on Lethal Autonomous Weapon Systems


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https://crsreports.congress.gov | IF11150 · VERSION 11 · UPDATED

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