Sarah Chang is a federal prosecutor who specializes in child exploitation crimes.

(Gérard DuBois for The Washington Post)

During my first week as a federal prosecutor of sexual abuse crimes against children, one of my colleagues told me her chief coping mechanism: Turn the sound off when you have to watch a video multiple times. This advice scared me. I imagined children screaming, crying and shrieking in pain — the stuff of nightmares.

My office is responsible for investigating and prosecuting such crimes, namely the production, possession and trafficking of child pornography. My first case file contained multiple CDs and DVDs showing a young girl being sexually abused by her father, who filmed his crimes with a handheld camera. Despite my colleague’s warning, I knew I couldn’t remain deaf during my first pass at the evidence. I went to our forensic computer lab and braced myself.

But all I heard was silence. The 5-year-old girl said nothing — not even a sob. Disturbed, I continued to watch each video with the sound on. I tried to beat back the silence by turning the volume up as high as it could go. The quiet was too deafening, too defeating to accept. Surely, these children must make a sound?

But in video after video, I witnessed silent suffering. I later learned that this is a typical reaction of young sexual abuse victims. Psychiatrists say the silence conveys their sense of helplessness, which also manifests in their reluctance to report the incidents and their tendency to accommodate their abusers. If children do disclose their abuse, their reports are often ambivalent, sometimes followed by a complete retraction and a return to silence.

The helplessness these children feel is rooted in the breach of trust they’ve experienced. Often, their abusers are people they expected would protect them. More than 80 percent of sexual abuse offenses against children are committed by people they know — parents, relatives, day-care providers and other trusted adults, according to the Justice Department. Studies show that children in those cases, particularly those abused by a parental figure, are more likely to recant their stories of abuse, if they report them at all.

[How child abuse hotlines hurt the very children they’re trying to protect]

Abusers often use explicit coercion or promises to compel children into silence. I see this dynamic often: A father, an uncle or a teacher, for instance, tells the child that the sexual abuse is an act of love and should remain secret. It’s an effective tactic. A 2014 study found that a child is more likely to maintain his or her promise to keep a parent’s secret if the child has a high degree of trust in the parent and believes that keeping a secret demonstrates trustworthiness. For children abused by someone they trust, this is particularly problematic. When familial intimacy and relationships of trust engender silence, children may not even realize that they are being abused.

But even when they do, loyalty keeps children from coming forward. Two years ago, I prosecuted a case in which a man in his late 30s sexually abused his daughter from ages 9 to 13. The truth came out only when his daughter befriended a school counselor — an adult she trusted outside of her abusive home. In her first interview with law enforcement, recorded on video, her speech was hesitant and her affect was shy. She repeatedly told officers that she didn’t want to talk about it, and she feared getting her father in trouble. He had told her that he would go to jail if she told anyone what they did together. Eventually, he confessed and pleaded guilty, receiving a sentence of 27 years.

The scope of this problem is enormous. The National Center for Missing and Exploited Children has reviewed more than 147 million images and videos of child pornography. About 9,600 victims have been identified (often, multiple images or videos exist of each child), though there are probably millions more suffering in silence. Technology has made it easier to match newly discovered pornographic images to known cases, so we know whether the abuse is ongoing or an old case in which the victim has been rescued. But even with advanced technologies and large databases, not every child can be identified. The perpetrators often scrub the images of all distinguishing information before they are distributed — no GPS coordinates, no date stamps, no make and model of the camera used, nothing.

While silence in the face of such horrific abuse often prevents its discovery, too much speech can cause its own problems. In the 1980s and 1990s, a series of failed prosecutions, such as the infamous McMartin Preschool case — in which day-care workers near Los Angeles were charged with raping and sodomizing dozens of small children, largely based on the children’s coerced, fabricated stories — drove researchers to examine the production of false memories in sex abuse cases. That research has been inconclusive, with some studies finding that children are very susceptible to suggested sex abuse memories and others concluding that this dynamic is rare.

Still, defense lawyers often accuse children who disclose abuse fluently and unflinchingly of being coached by law enforcement. It’s true that child sex abuse victims are rarely candid when they first talk about their experiences, but after repeated interviews — which are necessary in the criminal investigatory process — they can become well practiced and fall prey to accusations of having been coached. Unfortunately, this has come to have the opposite effect of the McMartin Preschool case, causing legitimate cases of abuse to be discounted.

In a case I prosecuted two years ago, I met a survivor about a year after she disclosed her father’s crimes against her. By then, she was a 15-year-old expert on how to speak with adults about sexual abuse. The criminal justice process, especially on the federal level, is slow and often asks victims to provide the same information in multiple settings to different investigating agencies. In contrast to her first recorded interview, she gave matter-of-fact answers in our meeting. I didn’t need to ask sensitively phrased, progressively more comprehensive questions. She knew how she was expected to identify the sex act: He put his penis inside her vagina. Her answers to questions were unfeeling and almost clinical.

Child sex abuse victims face a dilemma. To be recognized as victims, they cannot remain silent, but they must be silent enough to seem authentically hurt.

When I began prosecuting these crimes, I had to close the door to my office after viewing images of children being sexually abused. The images were devastating, leaving me visibly shaken. On some days, I had to look at 50 images, and on others, I viewed 300. Occasionally there was video, which I came to dread the most. Not only were the children silent, but also, in both the photos and video, their eyes were dead. I don’t know if that’s a result of survival, accommodation or fear. Maybe it’s all of those things.

We think silence can’t indicate that something hurts. Without an expression of pain, we assume there’s no injury. The pain scale at the doctor’s office displays a smiling face over a zero to represent no pain, while the worst pain, a “10,” is represented by a face crumpled in agony and tears falling. Too often, our society implicitly uses this scale to judge abused children’s emotional pain. If they’re not crying, if their faces are expressionless, we assume they must not be hurting. We refuse to hear silence as anything but a vacuum of feeling, a void in experience.

But in reality, a voiceless cry is often the most powerful one. Even though I encountered silence on many of the videos recorded by abusers, I decided that I would leave the sound on. Shielding my ears from the horrific acts done to these children would mute their pain and diminish my ability to give them a voice. One girl didn’t scream because her brother threatened to kill her. Another didn’t say anything because her father told her to keep it a secret. Regardless of what prompted it, the silence is deafening. It makes audible the psychological hold an abuser has over a child. Silence can be the most devastating evidence of sexual abuse; it can be the sound of pain itself.

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