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Corroborating Evidence

A jury’s confidence in the victim’s testimony recounting personal experience can be buttressed by careful corroboration of the victim’s storyline. Each storyline has multiple opportunities for corroboration. No detail is too insignificant to corroborate. For all trafficking survivors, socioeconomic factors, home conditions, family life, any disabilities, and previous forms of trauma and victimization are all important factors to consider.

For foreign nationals and certain legal permanent residents, the prosecutor should discuss the victim’s home country situation and vulnerabilities (e.g., economic, social, and educational status) that made the victim susceptible to leaving the home country for an opportunity in the United States. The prosecutor should ask about recruiting enticements, such as promises of employment, relationships, or success. If the victim was unable to earn a livable wage in the home country and was very poor, photographs of the living conditions, including housing where the victim resided, are useful. If the victim came via air, the prosecutor should obtain all documents related to the entrance, such as passports, visas, plane tickets, and arrival information. These documents can be introduced through a government or third-party neutral witness. If the victim entered the country on a temporary work visa, all applications and documents related to the employment-based recruitment should be sought. The prosecutor should consider using a factual or cultural expert witness to corroborate home country facts. For legal permanent residents and U.S. citizens, it may be especially important to address previous encounters with the government systems and how they have affected the individual, ranging from child welfare, foster care, and education to the criminal justice system.

Case Example: In 2014, Andrew Fields was sentenced to more than 30 years for sex trafficking and using drugs as a method of coercion to compel victims into prostitution.

Increasingly, human traffickers are using preexisting substance abuse addiction as a way to identify and recruit victims. This affects both foreign national and U.S. citizen victims. The prosecutor should consider using a medical expert witness to corroborate withdrawal symptoms. The home environment, relationship with family members, past domestic violence and abuse, and other forms of trauma and past victimization can be covered.

Witnesses are key sources for obtaining evidence and corroboration. Neighbors, friends, and customers may have information and are probable witnesses at trial. Investigators should interview all of these people immediately to avoid the possibility that they might coordinate their stories to discount the victim’s experience and might destroy evidence. Prosecutors often issue grand jury subpoenas for all of the following potential witnesses to nail down their statements under oath and to avoid surprises at trial:

  • Traffickers’ Family and Friends. Most of the traffickers’ family members and friends will be defense witnesses, but some may still be able to corroborate details of the victim’s story, such as employment in the household and timeframe when they knew the trafficker. In domestic servitude cases, prosecutors should identify and interview every person who lived or visited the trafficker’s house while the victim lived and worked there.
  • Neighbors. Witnesses who are neighbors almost always provide important corroboration for significant facts and may also receive a subpoena to testify before the grand jury, at trial, or both.
  • Other Victims. In multiple-victim cases, the testimony of other victims allows the jury to see the similarities between the victims, to the extent that each victim’s testimony provides a slightly different perspective of the same event.
  • Customers. Testimony from customers can corroborate the victim’s story.
  • Cooperating Defendants and Co-Conspirators. The testimony of cooperating defendants and co-conspirators is also helpful because these individuals offer an insider’s view of the trafficking situation.

Taking witness depositions, including those from victims, is rare in federal criminal practice and is limited to cases when the witness may be unavailable for trial because of extraordinary circumstances. A few states allow depositions of victims in criminal cases regardless of their availability as witnesses. If the standard is met, a video deposition will be taken, with all counsel present and stating objections as if the testimony were being presented at the trial. Before the video testimony is introduced at trial, the presiding judge will rule on the attorney’s objections, and the video will be redacted pursuant to the court’s rulings.
Other Corroborating Evidence
Many foreign national victims enter the United States via air, so there may be documentation of their entry, but not their departure, in a federal database at the Department of State (DOS) or the Department of Homeland Security (DHS). DOS maintains the Consular database. If there are no federal data indicating that the victim entered the United States, the victim could have entered by using another name and fraudulent documents, so prosecutors should think creatively about names that likely would tie the victim to the trafficker and should seek assistance from DOS.

Examples of corroborative evidence include the following:

Case Example: In U.S v. Justin Williams, the trafficker used Internet advertisements to aid in profiting from his sex trafficking operations. These advertisements were used as evidence in the case.

  • Immigrant records, including visa applications
  • Contracts
  • Recruitment correspondence
  • Paystubs, checks, or money deposits
  • Internet advertisements, social media posts, and online communication
  • Ledgers that can establish profit and daily monetary quotas that victims must earn and can be used to monitor income or customer contact information
  • Financial records such as MoneyPak or prepaid debit cards used by the victims to send earnings to the trafficker
  • Data from cellular phones, tablets, and computers that can include telephone numbers called or those that called the device; text messages to and from victims, potential recruits, fellow traffickers, and sex customers; photographs (of victims or places where the trafficker visited); an Internet search history; and even historical data regarding a phone’s location)
  • Hotel records because many "no-tell motels"  photocopy the drivers’ licenses of guests ("No-tell motels" generally offer increased anonymity, and can be used as a place for commercial sex.)
  • Medical records that document victims’ injuries, overdoses from forced drug ingestion or self-medication, exhaustion (and sicknesses that result from exhaustion and unhealthy living), venereal diseases, and forced abortions
  • Victim arrest records
  • Jail calls and visitor logs or bail bond records that substantiate the connection between a victim and a trafficker
  • Journals and diaries.

Multiple-Victim Cases

Case Example: U.S. v. Kil Soo Lee, a sweatshop factory case in American Samoa, involved more than 250 Vietnamese and Chinese victims, but only about 13 victims testified. Only a few victims could describe all of the events during the entire conspiracy period, but other victims' testimony corroborated specific elements, including a 72-hour lock-in at the factory and a severe beating at the factory directed by the defendant, resulting in serious injuries to some of the worker victims and trauma to all present on that day.

The good news about multiple-victim cases is that there are many witnesses. The bad news is that the victims must be located and interviewed. Multiple victims also provide options for choosing trial witnesses based on who can best present the facts at trial and best handle cross-examination. When making decisions about charges, a prosecutor should identify the victims who can best tell the entire story for inclusion in the indictment. Each of the other victim witnesses can describe unique facts or events observed only by that witness.

Multiple victims can corroborate each other, but they also can contradict each other. However, seemingly contradictory statements may not be a significant problem if the different recollections are not about important events or facts. Multiple victims may also have conflicts of interests that require careful coordination among service providers and law enforcement managing multiple interests.

For additional information, see the Resources page for Section 5.3, Victim Interview & Preparation.