Hidu, the electronic-sniffing dog, helps fight kiddie porn in pedophilia case in Mexico City

MEXICO CITY — An unusual alliance of international activist groups, Mexican prosecutors and a dog that was trained in Indiana to sniff out memory devices joined forces to catch a high-profile suspected pedophile in Mexico City.

It started when Free a Girl — a Netherlands group that fights human trafficking — tipped off activists with the U.S.-based Operation Underground Railroad that Jason Maatman, a Dutch man who openly advocated sex with children, had gone to Mexico after fleeing authorities in the Netherlands.

Maatman apparently thought lax Mexican law enforcement would allow him to operate freely in Mexico City.

But he didn’t count on Hidu, a recent graduate of a dog academy in Indianapolis that teaches canines to sniff out triphenylphosphine oxide, or TPPO, a chemical coating used in electronic devices like flash drives and memory cards.

“Three weeks ago, we learned that Nelson M. seemed to be active in Mexico and was a serious danger to children,” said Evelien Hölsken, the director of Free a Girl.

She said the group contacted Operation Underground Railroad “and asked if they could start an investigation.”

Mexican prosecutors were ready to work with the nongovernmental organizations.

Operation Underground Railroad set up a plan to lure Maatman into a trap, using the chat rooms and social media spaces he was active on.

“We were able to confirm he was in Mexico and then talking to him in just different chat rooms,” said Matt Osborne, OUR’s director of global operations. “He said, ‘I’m in a really kind of dangerous rundown area. I don’t want to give you my address. I don’t want you guys to come see me, but you can come meet me at a gas station.’ ”

So Mexico City prosecution detectives were waiting when Maatman showed up at a bus station — near a gas station — on the edge of the city’s main park on June 5.

Prosecutor Ernestina Godoy said Maatman was found to have a pistol and several doses of cocaine.

But the problem for prosecutors was that Maatman was caught at a bus stop — not at his home — and nobody knew were he was living. Nobody knew where he could have stashed any child sexual abuse material, which usually is kept in digital form.

City prosecutors used a network of street surveillance cameras to trace Maatman’s movements to a dingy apartment he was renting on the city’s rough east side. Tall and with reddish hair, the Dutchman stood out.

Once police obtained a search warrant, in came Hidu, a black Labrador retriever trained by Todd Jordan at Jordan Detection K9 academy in Indianapolis.

TPPO is a chemical used in small, solid-state memory devices to avoid overheating. There’s just enough of its distinctive odor for dogs to locate it.

Jordan started out training “accelerant-detection” dogs to look for evidence of arson. But the electronics-detection dogs he’s trained — 83 of them so far — have become more in demand because criminals now use flash drives to store everything from contacts to cryptocurrency used in drug deals.

“I think the electronics dogs have now surpassed the accelerant canines because of just the need of them and just because of the way the world is right now,” Jordan said.

Hidu was new at such work, having graduated just two weeks before and never been on a case.

O.U.R. flew Hidu and a handler to Mexico City, where prosecutors were about to search the apartment.

“My understanding is there was a cellphone hidden in a laundry basket with just rancid total terrible laundry, you know, dirty clothes in one corner that no one would go into,” Osborne said. “The dog found that phone.”

Hidu found more child porn material taped to a wall beneath a painting, Osborne said.

“The dog sniffed out a couple of the hard drives in a few places in his apartment that were difficult for humans to find, but the dog sniffed it out,” he said.

Prosecutors said the drives and devices contained about four terabytes of child sexual abuse material.

“Our understanding was that he was entertaining offers from other people who wanted to go into business with him,” Osborne said of Maatman, who is being held at a Mexico City prison on charges of human trafficking and drug and weapons possession.

Godoy credited Operation Underground Railroad and Hidu for their help.

“The message is clear for those who prey on a girl, a boy or an adolescent: In Mexico City, there will be no room for impunity and those that hurt or target them will be found, tried and sentenced,” Godoy said.

Still, Hölsken wants to know how Dutch authorities didn’t do more to curtail Maatman’s travel.

“Why was he not placed on an international wanted list?” she said.