In 1984 the photographer Tom Cahill smashed a plate-glass door in a fit of fury at the San Francisco Chronicle. He had just unsuccessfully attempted to get the paper's reporters to write about rape in America's jails and prisons. Cahill was a desperate man at the time, tormented by flashbacks and nightmares, his personal and professional life in ruins.

Cahill's story began in 1968, when he was arrested in Texas during a peaceful antiwar protest. An Air Force vet who opposed the Vietnam War, he did not prove popular among jail staff in the heavily military town of San Antonio. Before placing him in an overcrowded communal cell, he says, the guards spread word that he was a child molester. Cahill remembers with a shudder how one of the staff members shouted "fresh meat" before leaving. After 24 hours of beatings and gang rape, his life was shattered.

More than four decades later, sexual violence behind bars is still widespread in the United States. But thanks to Cahill and other courageous survivors, the ongoing crisis is no longer shrouded in silence.

The U.S. Department of Justice recently released its first-ever estimate of the number of inmates who are sexually abused in America each year. According to the department's data, which are based on nationwide surveys of prison and jail inmates as well as young people in juvenile detention centers, at least 216,600 inmates were victimized in 2008 alone. Contrary to popular belief, most of the perpetrators were not other prisoners but staff members—corrections officials whose job it is to keep inmates safe. On average, each victim was abused between three and five times over the course of the year. The vast majority were too fearful of reprisals to seek help or file a formal complaint.

Sexual violence is not an inevitable part of prison life. On the contrary, it is highly preventable. Corrections officials who are committed to running safe facilities train their staff thoroughly. They make sure that inmates who are especially vulnerable to abuse—such as small, mentally ill, and gay or transgender detainees—are not housed with likely perpetrators. And they hold those who commit sexual assaults accountable, even if they are colleagues.

But many corrections administrators are reluctant to make sexual abuse prevention a top priority, preferring to maintain the status quo rather than acknowledge the role their own employees play. Others are actually fighting reform efforts, claiming, in spite of the evidence, that sexual violence is rare.

This resistance is reflected in the slow implementation of the Prison Rape Elimination Act, which Congress unanimously passed in 2003. The law mandated binding national standards to help end sexual abuse in detention. But almost eight years later, the Justice Department has yet to promulgate final standards.

Attorney General Eric Holder has not shown leadership on this issue. In 2009 Holder essentially rejected standards recommended by a bipartisan commission that spent years studying the problem of prisoner rape, claiming that the recommendations—which included limits on cross-gender supervision and the loosening of deadlines for survivors to file formal grievances—would have been too expensive.

It's easy to feel numbed by the Justice Department's estimate that almost 600 prisoners are sexually victimized each day. But behind that number are real people like Jan Lastocy. While serving time for attempted embezzlement in a Michigan prison in 1998, Lastocy was raped. Not once, not twice, but several times a week for seven months. The rapist was an officer who supervised her at a prison warehouse. Lastocy was so afraid of him that she did not even dare to tell her husband of 30 years, John, what was going on. Later John said, "Jan did a stupid thing, and she went to prison for it. But no one should have to pay the price that she did."

Jan and John Lastocy's lives were devastated by prisoner rape. Holder should listen to and learn from them rather than bowing to corrections officials trying to maintain the status quo.

Lovisa Stannow (lstannow@justdetention.org) is executive director of Just Detention International.