The Prison Rape Elimination Act (PREA) of 2003 requires that federal, state and local correctional facilities maintain and enforce a zero-tolerance policy toward sexual assault for both inmate-on-inmate and staff-on-inmate misconduct.
Since 2003, the Bureau of Justice Statistics has been charged with completing a statistical review and analysis of the incidence and effects of prison rape for each calendar year. In 2011-2012, an estimated 4 percent of state and federal prison inmates and 3.2 percent of jail inmates reported experiencing one or more incidents of sexual victimization by another inmate or facility staff in the preceding 12 months or since admission to the facility. 
In fall 2009, at the request of the Attorney General, a PREA Working Group was convened to address the recommendations proposed by the National Prison Rape Elimination Commission. Staff from several Department of Justice (DOJ) components, including NIJ, worked together to review recommendations and draft a final rule.
On May 17, 2012, DOJ issued a final rule adopting national standards to prevent, detect and respond to prison rape, pursuant to PREA. The landmark rule sets national standards for four categories of facilities: adult prisons and jails, lockups, community confinement facilities, and juvenile facilities.
About the Prison Rape Elimination Act of 2003
Congress enacted the Prison Rape Elimination Act of 2003 (PREA) to address the problem of sexual abuse of persons in the custody of U.S. correctional agencies. PREA calls for Federal, State, and local corrections systems to have a zero-tolerance policy regarding prison rape (as defined by PREA) in prisons, jails, police lock-ups, and other confinement facilities.
Highlights of PREA include:
- Requires development of standards for detection, prevention, reduction, and punishment of prison rape.
- Standardizes collection and dissemination of information on the incidence of prison rape.
- Awards grants to help State and local governments implement the Act's provisions.
The Act applies to all public and private institutions that house adult or juvenile offenders and to community-based correctional agencies.
Prison Culture and the Perception of Rape
In response to the Prison Rape Elimination Act, NIJ first awarded a qualitative study to examine inmate perceptions of sexual violence in prisons. The Culture of Prison Sexual Violence study  is the largest ethnographic study of inmates ever conducted. The study examined how inmates perceive sexual relations in prison, including forced sexual misconduct. It covered men's and women's maximum security facilities in 15 States and included more than 600 hours of interviews. Inmates were not questioned about their own personal experiences or whether they were victims or perpetrators. Rather, they were asked questions about their knowledge of sexual violence in their facility and during their own incarcerations.
Overall, inmate reports indicate that they do not define or consider sexual relationships and rape in the same way that persons within free society view them, and, as a result, perceive rape to be a rare occurrence.
Concepts defining coerced and forced sexual behavior may be perceived differently in prison culture, but they are similar across all prisons in the United States. The researchers reported that 66 percent of male inmates and 71 percent of female inmates were aware of inmate-staff sexual relationships. Although no relationship between correctional staff and inmates is legal, these estimates included romantic, mutual relationships, not just rape.
Collectively, 9.1 percent of male and female inmates reported they were aware of an inmate who had been raped by a correctional staff member. Male and female inmates — about 34 percent and 28 percent respectively — reported they knew of an inmate who reported rape to staff members. A high percentage of both male and female inmates indicated that corrections officers try to protect inmates from being victimized.
This research yielded many recommendations for corrections practitioners that can be applied to both prisons and jails. These recommendations apply to staff training, inmate orientation, inmate observation, direct supervision, and policymaking.  Their implementation can contribute to changing both inmate and institutional culture .
State Responses to PREA
Another recently completed study funded by NIJ , examined the policies and practices of State corrections departments in response to PREA. From 2004 to 2005, 27 States reported specific written policies related to prison sexual violence, 19 of which comprehensively addressed prevention, investigation, response, and victim services. Several States also reported proactive efforts to involve the medical community in collecting rape kits for evidence, working with local district attorneys to promote prosecution of offenses, and invested in training staff to engage in investigations of allegations.
In addition to examining policies, the researchers in this study identified and conducted case studies on 11 States that might provide other practitioners with "the most informative lessons on addressing sexual violence in prison."  These States were: Connecticut, Idaho, Kansas, Maine, Massachusetts, Minnesota, Ohio, Oregon, Pennsylvania, Texas, and Utah. Synopses of these case studies can be found in the final report.
One way NIJ has responded to practitioners' needs is through research to develop risk assessment instruments to help identify potential victims or perpetrators of prison sexual violence. In one study, the researcher developed such a tool from analysis of official reports of incidents in Texas over a 4-year period. Although Texas has one of the highest incidence rates in the United States, it also has one of the lowest rates of substantiated cases. The extremely low base rate made construction of a validated risk-assessment instrument impossible, but the researcher identified potential victim characteristics and developed a checklist. He also identified best practices used by the Texas Safe Prison Program. 
[note 1] Beck, Allen, Marcus Berzofsky, Rachel Caspar, and Christopher Krebs, Sexual Victimization in Prisons and Jails Reported by Inmates, 2011-12. Washington, D.C.: U.S. Department of Justice, Bureau of Justice Statistics, 2013.
[note 2] Content on this page was excerpted from the National Institute of Corrections Online Clearinghouse on PREA, (accessed December 21, 2006). See PREA, Public Law 108–79, Sept. 4, 2003 (pdf) .
[note 6], [note 7] Zweig, J.M., R.L. Naser, J. Blackmore, and M. Schaffer, Addressing Sexual Violence in Prisons: A National Snapshot of Approaches and Highlights of Innovative Strategies, Washington, DC: U.S. Department of Justice, National Institute of Justice, 2007, NCJ 216856.
[note 8] Austin, J., T. Fabelo, A. Gunter, and K. McGinnis, Sexual Violence in the Texas Prison System, Washington, DC: U.S. Department of Justice, National Institute of Justice, 2006, NCJ 215774. The checklist is on pp. 24–25 of the report and the list of best practices is on page 26.