“Marcelo, I want you to study this topic carefully so that we know what to do.”

This was the order Pope Francis gave to Archbishop Marcelo Sanchez Sorondo, chancellor of the Pontifical Academy of Sciences and Social Sciences, to launch an investigation into modern-day slavery and systematic exploitation in the fishing industry.

Exploitation and abuses on the high seas is no narrow concern. The exportation of fish and other goods tainted by slavery and the exploitative treatment of workers to the United States has been widely reported. These seafood products have been traced to the supply chains and shelves of grocers like Kroger, Albertsons, Safeway, Walmart and Sysco, among others, and popular brands of canned pet food including Meow Mix, Fancy Feast and Iams.

In 2015, the Associated Press (AP) released the findings from its year-long investigation of slaves in the Indonesian Island of Benjina. Ultimately winning the 2016 Pulitzer Prize for Public Service, these reporters’ efforts remarkably helped free more than 2,000 slaves. Speaking with more than 40 current and former slaves, the AP was able to trace the journey of slave-caught seafood from its loading into trucks to its sale in Indonesia’s largest fish market, American supermarkets and pet food providers across the United States.

With expanding business, these slavery perpetrators have become increasingly desperate, kidnapping Burmese or Cambodian migrants, recruiting children and the disabled, and lying about wages to lure impoverished Thais. The process involves agents selling their slaves to Thai captains of fishing boats or the companies that own them for $1,000 per person. These victims of slave labor are then held under debt bondage. Thai boats are illegally registered to fish in Indonesia, often through bribing local officials, and the exploited workers are given false identification documents.

The United States considers Thailand one of its top seafood suppliers, purchasing nearly a fifth of the country’s $7 billion annual exports in the industry. The AP was able to trace, as closely as possible, this chain of fish tainted by exploitation being sold into US markets. For example, the AP followed the Silver Sea Reefer Company, a ship registered in Thailand, for 15 days to Samut Sakhon where workers packed seafood into over 150 trucks, one of which was marked by the Kinfisher Holdings Ltd. Every month, Kingfisher and its subsidiary KF Foods Ltd. ship 100 metric tons of seafood from Thailand to the United States to distributors (like Santa Monica Seafood and Stavis Seafoods on Boston’s fish pier) which then sell packages of seafood to large supermarkets.

Following the release of the AP investigation’s findings, Whole Foods and Walmart were among the companies accused of buying shrimp peeled at the hands of slave laborers, claims the companies deny. Costco was accused of having knowingly sold frozen prawns obtained through forced labor in Thailand, and the lawsuit was dismissed earlier this year.

Greenpeace also launched an investigation into the human rights violations of Thailand’s fishing industry by following 30 Cambodian men trapped by forced labor (5 of which died from subsequently contracting extreme disease). The seafood they were forced to catch ended up in Thai factories and were among the ingredients used by major pet food brands sold in the US, including Nestle Purina Petcare’s Fancy Feast and the J.M. Smucker Company’s Meow Mix. These human rights violations are indicative of a larger practice of labor abuse which taints other seafood products, including fish sauce, fish oil pills, fish sticks and shrimp.

Modern-day slavery on the high waters is further complicated by jurisdictional issues. The government whose flag the ship is registered under is responsible for ensuring that the ship’s operations are legal, but many ships are registered under countries more convenient for their intended malpractice. According to international law, countries receiving slave-made goods can take action against ships carrying out the offense yet this rarely happens. The situation is further compounded by the fact that ships carrying slave laborers can stay out at sea for a year or longer, with the practice of “motherships.” These boats, acting like “a floating city center," resupply boats with fuel, basic food and supplies to circumvent the need to dock on land, subsequently reducing chances of detection by authorities. Trawlers can stay in remote waters for indefinite periods of time, making them difficult to regulate or detect.

The highest ranks of the Catholic Church have made it their mission to put an end to this systematic exploitation and dehumanization of individuals at sea. I pray for the success of these new initiatives in tackling labor trafficking and debt bondage in the fishing industry. Pope Francis has been vocal about defending the voiceless, and modern-day slavery is just one of many injustices which has captured the Pontiff’s concern and lies at the heart of my own social justice and human rights work. Pope Francis puts it best: “It is impossible to remain indifferent to people who are treated as merchandise.”