Rotterdam Rats Are Being Trained to Sniff Out Crime

Photograph by Carolyn A McKeone/Getty Images

In New York, rats don’t get much love. Subway-dwelling rodents are being sterilized, and there’s even a recreational group of “ratters” who’ve trained their terriers and dachshunds to hunt down the critters. But in the Dutch port city of Rotterdam, rodents are being put to work—as crime fighters.

Rotterdam’s police have spent two years training a squadron of five rats to sniff out drugs, explosives, gunshot residue, blood, and other substances. The rodents, which reportedly have an average success rate of 95 percent, are all named after famous fictional detectives. There’s Magnum, Poirot, Derrick (named for the Oberinspektor in a German TV series), and Jansen and Janssen, the Dutch names for the bumbling, mustachioed duo from The Adventures of Tintin.

The five Rotterdam rat detectives won’t actually travel to crime scenes, and they won’t be permitted to crawl on suspects to sniff them out in the flesh. Instead, they’ll sniff clothes that have been handled by suspects to check for substances linked to criminal activity. “If a shooting were to take place today and several suspects were arrested, tests for gunshot residue would require chemicals, microscopes, and employees, all taking at least two hours,” Monique Hamerslag, who trained the rats, told Spiegel International. “Rats can do the same thing in two seconds.” (The police department has said that rats’ findings won’t be admissible in court but will be used to speed up searches.)

Rotterdam police hope the rats, which respond to simple verbal commands, will help eliminate costly lab tests and quickly narrow in on suspects.

Hamerslag came up with the idea for a rat police unit two years ago while studying animals used in crime scene investigations. Rats, it turns out, have put their highly sensitive noses to work for humans in the past. In Mozambique, giant “HeroRats” were successfully used to uncover more than 2,406 landmines, 992 bombs, and 13,025 small arms and ammunitions, clearing 6 million square meters of countryside. In Colombia, rats replaced some bomb-sniffing dogs. (The furry creatures have also been used to help doctors sniff out tuberculosis cheaply, but that’s another story.)

There is at least one downside to employing crime-fighting rats, however: Training them is time consuming, and most live only two or three years.

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