Elsewhere, in an encrypted social media chat group, a criminal posts screenshots of a hacked Bank of America checking account that’s up for sale. The account balance: $3,884. The owner’s full name, bank account number, phone number, address and access to her payment app are part of the deal—all for $3.

Welcome to the Dark Web. These are just a few of the scenes observed on a recent day by criminologist David Maimon as he tapped out a few keystrokes on his laptop and slipped into this hidden criminal world.

“This ecosystem is exploding,” says Maimon, whose Evidence-Based Cybersecurity Research Group at Georgia State University in Atlanta spies on crooks who steal billions of dollars a year. “We’re talking about enormous networks and organized criminal groups with sophisticated operations.”

In the nefarious corners of the internet, criminals talk to each other with complete anonymity. Here in the dark web, Maimon’s cybersleuths see it all—from stacks of stolen, washed and forged checks to pilfered driver’s licenses and purloined health insurance cards sold from one scammer to another. The personal identification information is often more valuable than the cash they can steal, Maimon says. “They can open new bank accounts, get fake driver’s licenses, buy guns. The stolen identity opens the door to any kind of financial activity,” he says.

The dark web is a group of hidden sites that can be accessed only with a special web browser that keeps users’ identities anonymous. You can’t get there via a Google search, for instance. Users can’t be traced, making the dark web attractive for criminals selling their stolen goods and illegal services.

 Maimon and his group have watched romance scammers using smartphone technology to alter their faces as they woo unsuspecting victims, observed crooks luring newcomers into the business with videos of thick wads of cash, and viewed homemade videos of criminals boasting about their successes. In one mysterious video the team found last fall, a man in a black and silver mask assures his clients he’ll be back “in business” soon. That business, Maimon says, mainly involves defrauding banks.

Maimon’s mission? To spot emerging trends so law enforcement and financial institutions can take action—and consumers can protect themselves. “To really stop it, you need to connect the dots by being out there with the criminals, understanding what they’re doing,” he says.

His group was among the first to sound the alarm, in 2021, about the avalanche of check-washing scams across the U.S. perpetrated by criminals who loot mailboxes and rewrite stolen checks. The scam costs Americans an estimated $815 million annually—and continues unabated. His team saw hundreds of stolen checks for sale online and on encrypted social media apps. “David kept raising red flags,” says Frank McKenna, chief fraud specialist for the fraud-detection company Point Predictive. “He put the whole story of check washing together.”

Maimon’s team spots emerging scam trends—and how criminals outsmart detection systems. “David’s research not only showcases how bad actors are scaling up fraud activity but also provides insight into the root causes of fraud,” says Karen Boyer, director of fraud intelligence, prevention and detection for M&T Bank.

The criminals he targets aren’t pleased. After Maimon was seen in media reports about check-washing scams, someone opened a bank account using his personal information—and sent a debit card to his home address as a warning. “It was scary,” he says. “The university sent a police officer for a month to make sure we were safe.”

Maimon has a PhD in sociology but was uninspired by work in that field. “I wanted to quit, until a colleague suggested studying cybercrime,” he says. “Nobody was doing meaningful research. We can study crime as it happens and make a difference. Every day is surprising and amazing.”