VI. International Human Rights Obligations
The United States is party to a number of international conventions that recognize rape as a human rights abuse, and require that the US ensure the protection of its citizens from sexual violence, including rape. Federal, state, and local governments must uphold these requirements under the US Constitution.
In 2010, the United Nations Human Rights Council adopted a resolution on efforts to eliminate all forms of violence against women, stressing that “States ... must exercise due diligence to prevent, investigate, prosecute and punish the perpetrators of violence against women and girls and provide protection to women and girls who have experienced violence, and that failure to do so violates and impairs or nullifies the enjoyment of their human rights and fundamental freedoms.” 
The US is party to the International Covenant on Civil and Political Rights (ICCPR), and to the Convention against Torture and Other Cruel, Inhumane or Degrading Treatment or Punishment (Convention against Torture), which both set out important standards for victims of rape.  The ICCPR guarantees the right to security of the person under article 9, which includes a right to protection of bodily integrity against third parties.  Both the Convention against Torture and the ICCPR (under article 7) guarantee the right to be free from torture and cruel, inhuman, or degrading treatment.  International tribunals and other bodies have established that rape is covered by the prohibitions on torture, and that the government must act to prevent rape and bring to justice those responsible.  The US is also a member of the Organization of American States, and as such is legally bound to protect and prevent violations of the rights contained in the American Declaration on the Rights and Duty of Man, including the right to life and security of the person. 
This obligation to protect individuals from harm is not limited to liability for action by or on behalf of governments. General international law and specific human rights treaties hold that states may be responsible for private acts if they fail to act with due diligence to prevent violations of rights or to investigate and punish acts of violence.
The United Nations Human Rights Committee (HRC) has made it clear that states party to the ICCPR and other conventions violate their obligation under these treaties not only when state actors are responsible for the action, but also when the state fails to take necessary steps to prevent violations caused by private actors. The HRC's General Recommendation 31 to the ICCPR notes that state parties must "take appropriate measures or … exercise due diligence to prevent, punish, investigate or redress the harm caused by such acts by private persons or entities."  The Committee Against Torture requires state parties to prevent and protect victims from gender-based violence and rape by exercising due diligence in investigating, prosecuting, and punishing perpetrators—even private actors—of rape and sexual assault. 
The Inter-American Court of Human Rights has reinforced that responsibility for violations of human rights rests with the state, as well as with the perpetrators when the state refrains from taking necessary measures to investigate crimes or prevent future violations:
An illegal act which violates human rights and which is initially not directly imputable to a state (for example because it is the act of a private person or because the person responsible has not been identified) can lead to international responsibility of the State, not because of an act itself, but because of the lack of due diligence to prevent the violation or to respond to it as required by the Convention.
Similarly, the Inter-American Commission of Human Rights, too has stated,
When the State apparatus leaves human rights violations unpunished and the victim’s full enjoyment of human rights is not promptly restored, the State fails to comply with its positive duty under international human rights law. The same principle applies when a State allows private persons to act freely and with impunity to the detriment of the rights recognized in the governing instruments of the inter-American system.
These provisions make clear that the US is bound to take all necessary possible measures to prevent sexual assault and rape even when carried out by private actors.
The principle of non-discrimination, the “backbone of the universal and regional systems for the protection of human rights,” also creates additional obligations to take steps to investigate, punish, and prevent rape.  Violence against women has been repeatedly recognized as one of the most extreme and pervasive forms of discrimination, severely impairing the ability of women to enjoy their rights. 
For example, the Convention on the Elimination of All Forms of Discrimination against Women (CEDAW), a treaty the US has signed but not ratified, obligates states parties to combat discrimination against women.  The Committee on the Elimination of Discrimination against women, the treaty body that interprets and monitors compliance with the CEDAW, has affirmed that gender-based violence is a form of discrimination against women and that state parties should have effective legal, preventive, and protective measures in place to provide justice for victims, hold offenders accountable, and protect society from future acts of sexual violence.  As a signatory to the treaty, the US is obliged to, at a minimum, not act in a way that would undermine the intent and purpose of the treaty. 
International and regional human rights systems have affirmed “the strong link between discrimination, violence and due diligence, emphasizing that a State’s failure to act with due diligence to protect women from violence constitutes a form of discrimination, and denies women their right to equality before the law.”
The European Commission on Human Rights has found that failure to protect women against violence breaches their right to equal protection of the law, even if the failure is unintentional. 
The Inter-American Commission on Human Rights has stated, “Ensuring that women can freely and fully exercise their human rights is a priority in the Americas,” since principles of non-discrimination and equal protection are fundamental to the Inter-American system. Following this reasoning, the commission has found that the US’s failure to act with due diligence to protect plaintiffs from domestic violence violated its obligation not to discriminate and to provide for equal protection under the law.
As with the duty to protect individuals from harm, the non-discrimination obligation applies even if the perpetrator is a private actor.  As former UN Special Rapporteur on Violence against Women Radhika Coomaraswamy stated in her first report on the subject in 1994,
In the context of norms recently established by the international community, a State that does not act against crimes of violence against women is as guilty as the perpetrators. States are under a positive duty to prevent, investigate and punish crimes associated with violence against women.
The positive duty to prevent and punish harm to individuals, including violence against women, requires that states act with due diligence to investigate acts of violence and hold offenders to account. The due diligence standard is expressed in a variety of legal instruments and other sources of international law.
The case law of human rights tribunals has helped clarify the practical requirements for diligent and thorough investigation of human rights violations. The European Court of Human Rights has made clear that the obligation under international law to protect the rights to life and bodily integrity entails the conduct of an effective official investigation when a violation occurs, so that the domestic laws that are intended to offer protection are effectively implemented.
An effective investigation has been defined as one that is capable of leading to the identification and punishment of those responsible. Authorities must take reasonable steps available to secure the evidence concerning the incident, including, inter alia, witness statements and forensic evidence. There must be effective access for the complainant to the investigation procedure. Any deficiency in the investigation that undermines its ability to establish the person or persons responsible will risk running afoul of the requirement to provide an effective remedy.
In M.C. v. Bulgaria, in 2003, the European Court of Human Rights held that the state failed to meet its obligations to establish and apply effectively a criminal-law system punishing rape when it failed to investigate sufficiently a “date rape” case due to the absence of traces of violence and resistance. In that case, despite authorities’ questioning of 17 persons (some repeatedly), and consulting experts, the court found the investigation inadequate because authorities failed to explore the possibilities for establishing the surrounding circumstances and did not sufficiently test the credibility of conflicting witness statements.
In Opuz v. Turkey, the European Court of Human Rights found local authorities failed to use the required diligence to prevent domestic violence recurring after terminating proceedings without conducting any meaningful investigation. The court found the state both failed in its obligation to prevent inhuman or degrading treatment and violated prohibitions on discrimination since domestic violence is regarded as gender-based violence, a recognized form of discrimination against women.
States in the Inter-American system have repeatedly been held internationally responsible for lack of due diligence in preventing human rights violations or investigating or sanctioning perpetrators. The Inter-American system too has made clear that it is not the formal existence of remedies that demonstrates due diligence, but rather that they are made available and effective. An investigation of alleged violations alone is not enough to clear the state of liability. Due diligence requires an effective search for truth by the state at its own initiative. The investigation must be serious, prompt, thorough, impartial, and in accordance with international standards in this area. Furthermore, any inquiry,
[M]ust be undertaken in a serious manner and not as a mere formality preordained to be ineffective.… Where the acts of private parties that violate the Convention are not seriously investigated, those parties are aided in a sense by the government, thereby making the State responsible on the international plane.
The affected parties must also have access to information about the development of the investigation. The Inter-American Commission has stressed that “The importance of due investigation cannot be overestimated, as deficiencies often prevent and/or obstruct further efforts to identify, prosecute and punish those responsible.”
Treating Survivors with Dignity
In considering states’ compliance with their duties to investigate cases, regional human rights bodies have recognized the importance of treating victims in a respectful and humane fashion.
The Inter-American Commission on Human Rights has noted that lack of respect for the dignity of victims or their families, a lack of sensitivity, and victim-blaming may have the effect of re-victimizing them and causing people to turn away from the justice system.  In a 2011 case against the US relating to domestic violence, the Inter-American Commission expressed concern that insensitive remarks from a dispatcher in Colorado in response to pleas for police action “result[ed] in a mistrust that the State structure can really protect women and girl-children from harm, which reproduces the social tolerance towards these acts.” 
The commission also underscored the internationally recognized principle providing that law enforcement officers, in the performance of their duties, “shall respect and protect human dignity and maintain and uphold the human rights of all persons.”
To prevent re-victimization, human rights bodies stress the importance of proper training of law enforcement officials so that they may learn to interact with victims in a way that fully respects their dignity. The Declaration on The Elimination of Violence against Women urges states to “take measures to ensure that law enforcement officers and public officials responsible for implementing policies to prevent, investigate and punish violence against women receive training to sensitize them to the needs of women.”
The Human Rights Council too has encouraged states to create gender-sensitized training for law enforcement. Training alone is insufficient: it must be accompanied by measures to monitor and evaluate results and to apply sanctions where agents do not comply with their responsibilities under the law. As an Inter-American Commission on Human Rights decision states, “Training is one side of the coin and accountability is the other.”
Due investigation, prosecution, and punishment are not only the required responses to violence against women, but also key means to prevent future violence.  Vigilantly and quickly prosecuting perpetrators conveys to offenders and the public that society condemns violence against women.  In contrast, not acting “serves to perpetuate the psychological, social, and historical roots and factors that sustain and encourage violence against women.” 
Since rape is a historically underreported crime, it is all the more important to respond effectively to those who do come forward. Failing to do so fosters an environment of impunity, confirms that such violence and discrimination is acceptable, and fuels its perpetuation—especially since some studies suggest that perpetrators of rape are frequently repeat offenders. The denial of an effective response by police both springs from and feeds into the perception that violence against women is not a serious crime.
Evidence of the MPD’s failure to investigate with due diligence sexual assaults, discussed in this report, calls into question whether the government is in violation of its obligations under international law.
The District of Columbia has laws and policies in place that would allow for humane treatment of victims and diligent investigation and prosecution of sexual assault crimes, but it is failing to effectively and consistently enforce them. It is time for it to do so.
The US Constitution states, “[A]ll treaties made, or which shall be made, under the authority of the United States shall be the Supreme Law of the Land; and the Judges in every State shall be bound thereby, anything in the Constitution or Law of any State to the contrary notwithstanding.” US Constitution, article VI, clause 2. Upholding this constitutional principle, the US Supreme Court has stated, “[I]nternational law is part of our law, and must be ascertained and administered by the courts of justice of the appropriate jurisdiction…” The Paquete-Habana, 175 U.S. 677, 700 (1900). Treaties of the United States have been held to be binding on states independent of the will and power of state legislatures. See Asakura v. City of Seattle, 265 U.S. 332 at 341 (1924) (holding that a treaty made under the authority of the United States stands on the same footing of supremacy as do the provisions of the Constitution and laws of the United States and “operate[s] of itself without the aid of any legislation, state or national; and it will be applied and given authoritative effect by the courts”).
 Human Rights Council, “Accelerating efforts to eliminate all forms of violence against women: ensuring due diligence in prevention,” A/HRC/14/L.9/Rev.1, June 16, 2010, para. 1.
 International Covenant on Civil and Political Rights (ICCPR), adopted December 16, 1966, G.A. Res. 2200 A(XXI), 21 U.N. GAOR Supp (No. 16) at 52, U.N. Doc. A/6316 (1966), 999 U.N.T.S. 161, entered into force March 23, 1976, ratified by the United States on June 8, 1992; the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment (Convention against Torture), adopted December 10, 1984, G.A. Res. 39/46, annex, 39 U.N. GAOR Supp. (No. 51) at197, U.N. Doc. A/39/51(1984), entered into force June 26, 1987, ratified by the United States on October 21, 1994.
 ICCPR, art. 9.
 ICCPR, art. 7; Convention against Torture.
See, for example, European Court of Human Rights (ECHR), Aydin v. Turkey, no. 57/1996/676/866, Judgment of September 25, 1997, http://www.unhcr.org/refworld/docid/3ae6b7228.html (accessed January 10, 2013), paras. 62-88; International Criminal Tribunal for the former Yugoslavia, Prosecutor v. Furundzija, Case No. IT-95-17/1-T, Judgment (Trial Chamber), December 10, 1998, paras. 163-86.
American Declaration of the Rights and Duties of Man, O.A.S. Res. XXX, adopted by the Ninth International Conference of American States (1948). In relation to US obligations to act with due diligence to prevent, investigate, sanction, and offer remedies in cases of violence against women perpetrated by private actors, Inter-American Commission on Human Rights (IACHR), Jessica Lenahan (Gonzales) et al. (United States), Report No. 80/11, Case 12.626, July 21, 2011, paras. 101-36. In this case, the Commission found that the US government, through the actions and omissions of its state agents in Colorado, failed to act with due diligence to protect three victims from domestic violence, in violation of obligations not to discriminate and to provide for equal protection before the law, and that the government also violated the right to judicial protection. See also in general for legal obligations on states to investigate sexual assaults with due diligence: IACHR, “Access to Justice for Women Victims of Sexual Violence in the Americas,” OEA/Ser.L/V/II, Doc. 68, January 20, 2007, pp. 10-48; IACHR, “Access to Justice for Women Victims of Sexual Violence in Mesoamerica,” OEA/Ser.L/V/II. Doc. 63, December 9, 2011, pp. 5-14.
 UN Human Rights Committee, General Comment 31, Nature of the General Legal Obligation imposed on States Parties to the Covenant, U.N. Doc. CCPR/C/21/Rev.1/Add.13 (2004), para. 9.
 UN Committee Against Torture (CAT), General Comment No. 2, Implementation of article 2 by States Parties, U.N. Doc. CAT/C/GC/2 (2008).
Inter-American Court on Human Rights (IACtHR), Velasquez-Rodriguez Case, Judgment of July 29, 1988, para. 172.
 The Inter-American Commission (IACHR), established by the American Declaration on the Rights and Duties of Man, co-exists with the Inter-American Court on Human Rights (IACtHR) and considers complaints about violations of the Declaration and the American Convention on Human Rights before they are referred to the court. See IACHR, Jessica Lenahan (Gonzales) et al. (United States), para. 173.
 IACHR, Jessica Lenahan (Gonzales) et al. (United States), para. 107.
 See for example, UN General Assembly, Declaration on the Elimination of Violence against Women, December 20, 1993, G.A. res. 48/104, 48 U.N. GAOR Supp. (no. 49) at 217, U.N. Doc. A/48/49 (1993) (“Affirming that violence against women constitutes a violation of the rights and fundamental freedoms of women and impairs or nullifies their enjoyment of those rights and freedoms.”); See also UN General Assembly, Resolution 64/137, “Intensification of efforts to eliminate all forms of violence against women,” A/RES/64/137, February 11, 2010 (“Stressing that States have the obligation to promote and protect all human rights and fundamental freedoms for all, including women and girls, and must exercise due diligence to prevent and investigate acts of violence against women and girls and punish the perpetrators, to eliminate impunity and to provide protection for victims, and that failure to do so violates and impairs or nullifies the enjoyment of their human rights and fundamental freedoms.”).
 Convention on the Elimination of All Forms of Discrimination against Women (CEDAW), adopted December 18, 1979, G.A. res. 34/180, 34 U.N. GAOR Supp. (No. 46) at 193, U.N. Doc. A/34/46, entered into force September 3, 1981. The United States signed CEDAW in 1980 but has not ratified.
 UN Committee on the Elimination of Discrimination against Women, General Recommendation 19, Violence Against Women, UN Doc. A/47/38 (1992), para. 24(t).
 Vienna Convention on the Law of Treaties, adopted May 23, 1969, entered into force January 27, 1980, art. 18.
 IACHR, Jessica Lenahan (Gonzales) et al. (United States), paras. 110-111; UN General Assembly, Declaration on the Elimination of Violence against Women, art. 4(c)(urging States to “exercise due diligence to prevent, investigate and, in accordance with national legislation, punish acts of violence against women, whether those acts are perpetrated by the state or against private persons.”).
 ECHR, Opuz. v. Turkey, (Application no. 33401/02), judgment of June 9, 2009, para. 191.
 IACHR, “The situation of the rights of women in Ciudad Juarez, Mexico: the right to be free from violence and discrimination,” (“Cuidad-Juarez”), Inter-Am.C.H.R., OEA/Ser.L/V/II.117, Doc. 44 (2003), paras. 99-100.
 IACHR, Jessica Lenahan (Gonzales) et al. (United States), paras. 173, 212.
 UN Committee on the Elimination of Discrimination against Women, General Recommendation 19, Violence Against Women, UN Doc. A/47/38 (1992) (“States may also be responsible for private acts if they fail to act with due diligence to prevent violations of rights or to investigate and punish acts of violence, and for providing compensation.”); UN General Assembly, Declaration on the Elimination of Violence against Women (States should “exercise due diligence to prevent, investigate and, in accordance with national legislation, punish acts of violence against women, whether those acts are perpetrated by the State or by private persons.”).
 UN Commission on Human Rights, Preliminary Report Submitted by the Special Rapporteur on violence against women, its causes and consequences, E/CN.4/1995/42, November 22, 1994, para. 72.
 See, for example, UN Commission on Human Rights, Report of the Special Rapporteur on violence against women, its causes and consequences, Yakin Erturk, E/CN.4/2006/61, January 20, 2006, paras. 19-29 (concluding that customary law requires states to prevent and respond to acts of violence with due diligence); See above, UN Human Rights Council, “Accelerating efforts to eliminate all forms of violence against women: ensuring due diligence in prevention,” A/HRC/14/L.9/Rev.I, June 16, 2010; UN Committee on the Elimination of Discrimination against Women, A.T. v. Hungary, Communication No. 2/2003, January 26, 2005; IACHR, Jessica Lenahan (Gonzales) et al. (United States), paras. 122-124; IACtHR, Velasquez Rodriguez Case, para. 172.
 For the Court’s repeated findings on the obligation to investigate, see, among others, Jordan v. the United Kingdom, no. 24746/94, Judgment of May 4, 2001; Isayeva v. Russia, no. 57950/00, Judgment of February 24, 2005; and Adali v. Turkey, no. 38187/97, Judgment of March 31, 2005.
 ECHR, M.C. v. Bulgaria, no. 39272/98, Judgment of December 4, 2003, paras. 119, 153, 177-87.
 ECHR, Opuz v. Turkey, (Application no. 33401/02), Judgment of June 9, 2009, paras. 74, 75, 169, 191, 200.
 See, for example, Ibid.; IACHR, Maria da Penha Maia Fernandes (Brazil), Report No 54/01, Case 12.051, April 16, 2001.
 IACHR, Jessica Lenahan (Gonzales) et al. (United States), para. 181.
 IACtHR, Velasquez Rodriguez case, para. 177.
 IACHR, “Cuidad Juarez”, paras 143-146.
 Ibid., para. 137.
 IACHR, “Access to Justice for Women Victims of Violence in the Americas,” OEA/Ser.L/V/II, Doc. 68, January 20, 2007, paras. 172-176.
 IACHR, Jessica Lenahan (Gonzales) et al. (United States), para. 167.
 IACHR, “Access to Justice for Women Victims of Violence in the Americas,” paras. 132, 134.
 UN General Assembly, Declaration on the Elimination of Violence against Women, art. 4(i).
 UN Human Rights Council, “Accelerating efforts to eliminate all forms of violence against women: ensuring due diligence in prevention,” A/HRC/14/L.9/Rev.I, June 16, 2010.
 IACHR, “Ciudad Juarez,” para. 156.
 Ibid., para. 153.
 UN Committee on the Elimination of Discrimination against Women, Fatma Yildirim v. Austria, Communication No. 6/2005, CEDAW/C/39/D/6/2005, August 6, 2007, para. 12.3(b).
 IACHR, Maria Da Penha Maia Fernandes (Brazil), para. 55.
 See, for example, David Lisak and Paul M. Miller, “Repeat Rape and Multiple Offending Among Undetected Rapists,” Violence and Victims, vol. 17, no. 1, 2002.
 IACHR, “Ciudad Juarez,” para. 36.