Constitutional Provisions

A number of constitutional provisions, especially certain rights contained in the Bill of Rights, are relevant to the use of force in law enforcement. Notably, the Fourth Amendment stipulates that:

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated.

This institutes a right to bodily security and prevents arbitrary arrest, and also sets a standard of reasonableness for the use of force when arresting any individual. Further, according to the Eighth Amendment:

Excessive bail shall not be required, nor excessive fines imposed, nor cruel and unusual punishments inflicted.

This effectively precludes grossly excessive use of force by law enforcement officials in a custodial setting. 

More detailed constraints on use of force are set out in the laws of the individual states and the rules governing their law enforcement agencies, as well as in the judgments of the United States Supreme Court.

Under the First Amendment, Congress shall make no law abridging the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.

Treaty Adherence

Global Treaties

Adherence to Selected Human Rights Treaties

1966 Covenant on Civil and Political Rights (ICCPR)

State Party
ICCPR Optional Protocol 1 Not party
1984 Convention against Torture (CAT) State Party
Competence of CAT Committee to receive individual complaints No
CAT Optional Protocol 1 Not party
Adherence to International Criminal Law Treaties
1998 Rome Statute of the International Criminal Court Not party

Regional Treaties

Adherence to Regional Human Rights Treaties

1948 Charter of the Organization of American States

State Party
1969 Inter-American Convention on Human Rights Not party
Competence of Inter-American Court on Human Rights N/A

National Legislation

Police Use of Force

Two US Supreme Court judgments are especially relevant to police use of force. In its 1989 judgment in the case of Graham v. Connor, the Supreme Court clarified the basic US legal standard for determining legality of any use of force by a law enforcement official: whether his or her actions were "objectively reasonable". This assessment must be made from the perspective of a reasonable officer on the scene, including what the officer knew at the time.US Supreme Court, Graham v. Connor, 490 US 386 (1989), Decided on 15 May 1989, at 396.

With respect to the use of firearms, in its landmark 1985 judgment in Tennessee v. Garner the Supreme Court held that:

This case requires us to determine the constitutionality of the use of deadly force to prevent the escape of an apparently unarmed suspected felon. We conclude that such force may not be used unless it is necessary to prevent the escape and the officer has probable cause to believe that the suspect poses a significant threat of death or serious physical injury to the officer or others.US Supreme Court, Tennessee v. Garner, 471 US 1 (1985), Decided on 27 March 1985.

This is a rather lower threshold than the international standard, which does not allow use of firearms other than in a grave threat to life unless the threat is imminent. In contrast, in 2014, the US Customs and Border Police published a new Use of Force Policy and Manual that does respect international law, stating that

use of deadly force is “necessary” when the officer/agent has a reasonable belief that the subject of such force poses an imminent danger of death or serious physical injury to the officer/agent or to another person.

A valuable website on police department regulations across the United States on use of force, the Use of Force Policy Database, is available here.

With regard to the use of a conducted energy device, such as a Taser, the leading case to date is the 2016 judgment of the Court of Appeal for the Fourth Circuit in Armstrong v. Village of Pinehurst. The standard, which the US Supreme Court subsequently declined to overturn, is that use of such weapons “are proportional force only when deployed in response to a situation in which a reasonable officer would perceive some immediate danger that could be mitigated by using the taser.”US Court of Appeals for the Fourth Circuit, Armstrong v. Village of Pinehurst, Judgment (Case No. 15-1191), 11 January 2016, p. 21.It  further stated that: “Force that imposes serious consequences requires significant circumscription”.


In August 2019, California adopted a new law governing use of deadly force. The new law, which came into force on 1 January 2020, provides that law enforcement officials will only be allowed to discharge a firearm if he or she “reasonably believes ... that deadly force is necessary to defend against an imminent threat of death or serious bodily injury". This meets international law and standards.

The change was prompted by the shooting of an unarmed black man, Stephon Clark, 22, in Sacramento in March 2018. Mr Clark was reportedly shot eight times by two police officers, who claimed to have mistaken Mr Clark's phone for a gun's muzzle flash. The officers will not be prosecuted. 

Use of Force in Custodial Settings

Use of force in custodial settings is subject to similar constraints as other law enforcement actions. A leading case decided by the Supreme Court in recent years is Kingsley v. Hendrickson, which concerned the use of force against pre-trial detainees. In its 2015 judgment, the Court declared that “individuals awaiting trial are particularly vulnerable to government abuse and should not be forced to prove that their alleged abusers intended to harm them in order to claim their rights were violated.” The case concerned use of a Taser against Mr Kingsley, who was on pre-trial detention on drugs charges. In earlier jurisprudence, the Court had ruled that force was only unlawful if it reflected a subjective “deliberate indifference” on the part of prison officers.

For convicted prisoners, the applicable standard remains that set out in 1986 by the Supreme Court in Whitley v. AlbersThe Court held that to establish that the use of force was excessive under the Eighth Amendment, convicts must show that it constituted an “unnecessary and wanton infliction of pain”. Whether this will be amended to bring the standard into lie with Kingsley v. Hendrickson the next time a pertinent case comes before the Supreme Court is moot.

Police Oversight

External oversight of the police and other law enforcement agencies is typically provided by citizen review boards, police commissions, investigatory agencies, and monitors.Merrick Bobb, "Internal and External Police Oversight in the United States", at:

In addition, the US Department of Justice is able to conduct "pattern or practice" investigations, where there is evidence of a widespread problem with a particular police department.As Bobb recalls, in "the wake of the Rodney King incident in Los Angeles [in 1991], the Congress of the United States passed legislation enabling the Civil Rights Division of the Department of Justice to commence investigations of state and local police alleged to be engaging in an unconstitutional pattern or practice of excessive force or other serious misconduct. If the federal investigation shows that allegations are true, a federal court is empowered to compel police reform by issuing an injunction."Notably, it has done so with respect to the Baltimore Police Department, the Chicago Police Department, and the Ferguson Police Department, among others. In January 2017, the Department of Justice reported that, since 2009, its Civil Rights Division had opened 25 investigations into law enforcement agencies and was enforcing 19 agreements, including 14 consent decrees and 1 post-judgment order. 

In April 2021, the US Attorney General, Merrick Garland, announced an investigation into the use of force by the Minneapolis Police Department.



Views and Concluding Observations of United Nations Treaty Bodies

In its List of Issues for the US's next periodic report on its implementation of the ICCPR, the Human Rights Committee asked for the following detail on police use of force:

Please indicate what steps the State party is taking to limit excessive use of force by law enforcement officials against civilians, particularly those belonging to racial minorities. Describe the mechanisms in place to hold law enforcement officials who use excessive force accountable, and include data on the investigations and prosecutions pursued in cases of firearm use by law enforcement officials. Indicate the relevant laws and describe the legal standards under domestic law on the appropriate use of force and firearms by law enforcement and security forces during arrest, during demonstrations, in custody, in anti-terrorism or anti-poaching operations, and under any other circumstances where force may be used. Explain how such laws are compliant, in law and in practice, with the Basic Principles on the Use of Force and Firearms by Law Enforcement Officials. Please comment on reports that nine states and Washington, D.C. do not have laws on the use of lethal force by their law enforcement officials.

In 2014, the Human Rights Committee expressed its concern 

about the still high number of fatal shootings by certain police forces, including, for instance, in Chicago, and reports of excessive use of force by certain law enforcement officers, including the deadly use of tasers, which has a disparate impact on African Americans, and use of lethal force by Customs and Border Protection (CBP) officers at the United States-Mexico border....Human Rights Committee, Concluding Observations on the United States' fourth periodic report, UN doc. CCPR/C/USA/CO/4, 23 April 2014, §11.

The Committee welcomed the 2014 Customs and Border Protection (CBP) standard on use of firearms, which now complies with international law. The Committee called on the United States to:

(a) Step up its efforts to prevent the excessive use of force by law enforcement officers by ensuring compliance with the 1990 Basic Principles on the Use of Force and Firearms by Law Enforcement Officials;

(b) Ensure that the new CBP directive on the use of deadly force is applied and enforced in practice; and

(c) Improve reporting of violations involving the excessive use of force and ensure that reported cases of excessive use of force are effectively investigated; that alleged perpetrators are prosecuted and, if convicted, punished with appropriate sanctions; that investigations are re-opened when new evidence becomes available; and that victims or their families are provided with adequate compensation.Human Rights Committee, Concluding Observations on the United States' fourth periodic report, UN doc. CCPR/C/USA/CO/4, 23 April 2014, §11.

Also in 2014, the Committee against Torture expressed similar concerns about excessive and discriminatory use of force by US law enforcement agencies. It noted its concern about:

the numerous reports of police brutality and excessive use of force by law enforcement officials, in particular against persons belonging to certain racial and ethnic groups, immigrants and LGBTI individuals.Committee against Torture, Concluding Observations on the United States' third to fifth periodic report, UN doc. CAT/C/USA/CO/3-5, 19 December 2014, §26.

It further expressed 

deep concern at the frequent and recurrent shootings or fatal pursuits by the police of unarmed black individuals.Committee against Torture, Concluding Observations on the United States' third to fifth periodic report, UN doc. CAT/C/USA/CO/3-5, 19 December 2014, §26.

The Committee called on the United States to:

(a) Ensure that all instances of police brutality and excessive use of force by law enforcement officers are investigated promptly, effectively and impartially by an independent mechanism with no institutional or hierarchical connection between the investigators and the alleged perpetrators;
(b) Prosecute persons suspected of torture or ill-treatment and, if found guilty, ensure that they are punished according to the gravity of their acts;
(c) Provide effective remedies and rehabilitation to the victims;
(d) Provide redress for Chicago Police Department torture survivors by supporting the passage of the ordinance entitled Reparations for the Chicago Police Torture Survivors.Committee against Torture, Concluding Observations on the United States' third to fifth periodic report, UN doc. CAT/C/USA/CO/3-5, 19 December 2014, §26.

With respect to the use of Tasers, the Committee made detailed recommendations, calling on the United States to:

ensure that electrical discharge weapons are used exclusively in extreme and limited situations — where there is a real and immediate threat to life or risk of serious injury — as a substitute for lethal weapons, and by trained law enforcement personnel only.

It further urged the United States to

revise the regulations governing the use of such weapons, with a view to establishing a high threshold for their use, and expressly prohibit their use on children and pregnant women.

The Committee was also "of the view" that

the use of electrical discharge weapons should be subject to the principles of necessity and proportionality and should be inadmissible in the equipment of custodial staff in prisons or any other place of deprivation of liberty. The Committee urges the State party to provide more stringent instructions to law enforcement personnel authorized to use electric discharge weapons, and to strictly monitor and supervise their use through mandatory reporting and review of each use.Committee against Torture, Concluding Observations on the United States' third to fifth periodic report, UN doc. CAT/C/USA/CO/3-5, 19 December 2014, §27.


The United States is not a state party to the 1969 American Convention on Human Rights and has not accepted the jurisdiction of the Inter-American Court of Human Rights. 


In April 2021, Derek Chauvin was found guilty of murder of George Floyd by a Minneapolis court.

The leading cases of Graham v. Connor, Tennessee v. Garner, Kingsley v. Hendrickson, and Armstrong v. Village of Pineburst are discussed above. Each is available for download below.

Kisela v. Hughes

In an April 2018 judgment, the Supreme Court ruled in favour of an Arizona police officer who shot a woman outside her home in May 2010. Officer Andrew Kisela shot Amy Hughes four times after she emerged from her house holding a kitchen knife at her side and did not comply with commands to drop it. Hughes sued Kisela claiming the officer used excessive force, but the Supreme Court ruled this week that Kisela was entitled to qualified immunity, a legal doctrine that says police are immune from excessive-force lawsuits as long as they do not violate “clearly established” rights.

In a dissenting opinion, Justice Sotomayor (Justice Ginsburg agreeing) held that Mr Kisela’s use of force was unreasonable and unconstitutional. Moreover, he had had fair notice that he was acting unlawfully, in circumstances where Ms Hughes posed no objectively reasonable threat to those around her, and had not been given a warning of the imminent use of a significant degree of force. 

Redmond v. Crowther

In a February 2018 decision by the Court of Appeal for the Tenth Circuit, it was reaffirmed that negligence by prison officers was insufficient to ground a claim for excessive use of force. The case concerned use of tear gas in a recreation yard against one particular prisoner, but which was drawn in by the prison ventilation system intake vent, affecting other prisoners:

when prison officials deployed the gas, the intake vent drew the gas in and filtered it into the prison. Numerous prisoners in their cells were exposed to the gas, which caused a burning sensation in their eyes, ears, and noses, and made it difficult for them to breathe.US Court of Appeal for the Tenth Circuit, Redmond v. Crowther, Case No. 16-4131, Decided on 9 February 2018.

Civil Society

The University of Chicago has assessed the compatibility of law enforcement policies in 20 US cities. Of the 20 city police departments surveyed, not one met the minimum standards established by human rights law. Even the two cities that had the best scoring policies, Chicago and Los Angeles, did not guarantee basic safeguards (i.e. necessity, proportionality and accountability) in the law.  "Deadly Discretion" is available for download below or on the University of Chicago website here.

In April 2021, an independent international commission of inquiry report concluded that discriminatory and excessive use of force against African Americans pervaded policing in the United States. The report even asserted that crimes against humanity might have been committed. 


Constitution of the United States of America

US states rules on lethal force assembled by Amnesty International

US Supreme Court Graham v. Connor (1989)

US Supreme Court Tennessee v. Garner (1985)

California Draft Police Use of Force Law (2019)

US Court of Appeals Armstrong v. Village of Pinehurst (2016)

US Supreme Court Kingsley v. Hendrickson (2015)

US Department of Justice Baltimore PD Report (2016)

US Department of Justice Chicago PD Report (2017)

US Department of Justice Ferguson PD Report (2015)

US Court of Appeals (10th Circuit) Redmond v. Crowther (2018)

US Supreme Court Kisela v Hughes (2018)

The Failure of Police Use of Force Policies to Meet Fundamental Human Rights Standards

Independent International Commission of Inquiry Report (April 2021)

University of Chicago Law School "Deadly Discretion" Report on Law and Policy in 20 US Cities (2020)