State authorities have unleashed a four-legged investigator specifically trained to sniff out digital electronics commonly used by sexual predators to exploit children and others.

K-9 Sota, a black British Labrador, was introduced to the public last week by the state Department of Public Safety (DPS) as the first law enforcement dog in Minnesota able to detect cellphones and various data storage devices such as USB drives and micro SD cards, where evidence might be hidden that would help prosecutors in their pursuit to lock up sex crime perpetrators.

Dogs with Sota's talents have not been around all that long. There were just three like her in the United States two years ago, according to the DPS. That number has surged to about three dozen.

Dogs like Sota can recognize a chemical coating on memory storage chips called triphenylphosphine oxide, more commonly known as TPPO.

"K-9 Sota is trained to help find tiny pieces of plastic that may contain critical evidence in a case," said Drew Evans, superintendent of the Bureau of Criminal Apprehension (BCA).

Holding up a tiny memory storage chip during a news briefing with Sota and her handler, Evans described a scenario from a recent investigation.

If a criminal "took an item of evidence this small and you just threw it out into the grass and ran out of the house as we're there, it would be very difficult for any of us to find," he said. "She can find it readily and very quickly for us."

Since Sota started her work in May, she has been deployed on 10 investigations including predatory crimes, homicides, financial offenses and other cases that involve digital information storage devices.

She has located 21 pieces of potential electronic evidence, including a meticulously hidden cellphone from one homicide case, Evans said.

BCA special agent Lucas Munkelwitz is Sota's partner. He works in the agency's predatory crimes section.

"BCA agents first sweep a scene for any obvious evidence, and then we send in K-9 Sota," Munkelwitz said.

But a human's five senses during those sweeps for evidence can fail to find what a dog's nose can, Evans said.

"Years ago, when electronic evidence was becoming more prevalent, they were in very large computers," he said.

"We knew where they were. [But] as we all transitioned to all of us having a smartphone [and] all of us having evidence that is this small that is inserted into a phone, criminals are very well adept. They know we are looking for this evidence.

"This dog is really going to take us years forward," Evans said, "because her nose is much better, obviously, than any of ours."

The BCA received Sota thanks to the nonprofit Operation Underground Railroad, a nonprofit that fights sex trafficking.

The California-based organization paid about $15,000 to buy and train her. The BCA covers the bills for her kennel, food and work equipment.

Paul Walsh • 612-673-4482