A Federal Prosecutor’s Journey into Blockchain Intelligence at the Department of Justice

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Jessica Peck, a senior counsel in the US Department of Justice (DOJ), didn’t start her career with blockchain intelligence in mind. Her path, though, led her from prosecuting violent crimes in New York City to unraveling some of the most complex crypto-enabled cases the DOJ has tackled. 

Today, Peck serves as an Acting Assistant Deputy Chief within the DOJ’s Computer Crime and Intellectual Property Section (CCIPS), where she is a key player in combating cybercrime. Her journey reveals the curiosity, adaptability, and commitment that make federal prosecutors essential to protecting the public.

From violent crimes to cyber investigations

Peck’s career began as a young prosecutor in the Manhattan District Attorney’s Office. “I went straight into the DA’s Office after law school,” she recalled. “My early cases were mostly gun crimes, drug crimes, and attempted murders. You’re in the thick of things, chasing down every piece of evidence you can find.” 

For Peck, each violent crime investigation was an exercise in precision, focused on gathering every relevant detail. “In a violent crime case, you know exactly where and when the crime happened and so the universe of evidence is relatively finite. You find your evidence, you locate your perpetrator, you interview every witness you can find, and you bring charges,” she said.

But her focus shifted unexpectedly when she was handed her first financial crime case: a long-term investigation that introduced her to the slower, meticulous nature of tracking digital evidence. “I fell in love with the puzzle of it,” Peck explained. “It’s so different from violent crime cases, where everything’s fast-paced. Here, I was working on cases that required time, patience, and technical knowledge.” This new challenge excited her and led her to join the Manhattan DA’s Cybercrime and Identity Theft Bureau (CITB).

A first glimpse at blockchain cases

Peck’s first encounter with cryptocurrency came through a case that would test her newly acquired cyber skills. 

In 2017, she was assigned to a case involving a kidnapping and burglary. The suspect had orchestrated the abduction of his own uncle to steal a Ledger Nano X, a small USB-like device holding USD 1.2 million in Ether. “When I was first assigned to the case, I remember thinking, ‘What is Ether, and how do we figure out where it’s going?’” Peck explained. “I had no idea how we were going to handle it, but I was ready to learn.”

The case revealed the intricate world of blockchain tracing, a field Peck would later help progress. She described her first time seeing blockchain tracing software in action as “mind-blowing.” “The software could track funds across wallets, transactions, and exchanges. I remember thinking, ‘This is the future of crime investigation.’” 

With her team, Peck traced the stolen Ether through an exchange, catching the suspect in the act of trying to cash out the funds. The experience left her fascinated with the potential of blockchain intelligence in prosecution. “It wasn’t just a one-time tool for us,” she said. “It was a new avenue for tracking criminal activity that hadn’t been possible before.”

Joining the DOJ and shaping blockchain intelligence investigations

As Peck’s interest in digital assets deepened, her career took another significant turn when she joined the DOJ’s Computer Crime and Intellectual Property Section (CCIPS). As a prosecutor in CCIPS, she found herself diving deeper into the complexities of cyber-enabled crimes. “I came to CCIPS excited and willing to work on any type of case,” she said. “Crypto, cyber, intellectual property — you name it. I just wanted to learn as much as possible.”

At the DOJ, Peck joined the National Cryptocurrency Enforcement Team (NCET), an interdisciplinary group dedicated to addressing crypto-related crimes. Within NCET, Peck focused on building protocols for blockchain intelligence and developing strategies to track illicit activities through cryptocurrency transactions — often in partnership with other agencies, such as the FBI, IRS, and US Secret Service. 

Peck explained that she was particularly passionate about NCET’s collaborative approach. “One of the best parts of NCET is that we’re not working alone,” she noted. “We have attorneys all over the country and experts from other federal agencies. We’re constantly sharing knowledge, which makes us more effective and adaptive to new threats.”

During her time with NCET, Peck has worked on various groundbreaking cases. One that stands out was a hack of a cryptocurrency exchange. “Watching the subsequent money laundering transactions was like watching financial chess unfold in real-time,” she said. “We were tracing funds moving at lightning speed across borders and platforms.” In cases like these, Peck and her colleagues rely on blockchain tracing tools to visualize money flows, uncovering how funds were strategically moved to evade detection. “Blockchain software gives us patterns, and those patterns are everything in a case like this. Without them, we’d be in the dark.”

Building a support network for blockchain prosecution

Beyond her caseload, Peck actively contributes to a collaborative environment within the DOJ, sharing insights and building connections with attorneys focused on crypto-related cases. 

As part of her work with NCET, Peck supports the efforts of the Digital Asset Coordinator (DAC) network, a DOJ initiative that connects attorneys nationwide on crypto-related cases. “DAC is all about building expertise,” Peck explained. “We have attorneys who are tackling these cases for the first time, and they need resources, training, and mentors. I want every prosecutor to feel like they’re not alone in this.”

Peck and her colleagues also regularly train other attorneys and partner, both domestically and abroad, with agencies to ensure a consistent approach to blockchain intelligence. “We’re working with the best minds in cybercrime, and we’re constantly learning from each other,” she said. “The more we share our experiences, the better we all become at tackling crypto cases.”

A vision for the future of blockchain in law enforcement

Looking to the future, Peck explained that she believes blockchain intelligence will be an indispensable part of law enforcement. “Blockchain has opened up a whole new world for prosecutors,” she said. “With this technology, we have transparency we’ve never had before. I truly believe it will become a core part of every prosecutor’s tool kit.” Her vision includes an expansion of blockchain training and a deeper integration of blockchain tracing tools, which she sees as critical for staying ahead of increasingly sophisticated cybercriminals.

Jessica Peck’s career is a testament to the impact that curiosity and adaptability can have in the face of emerging threats. From her first brush with blockchain in the form of a stolen Ledger Nano X to leading complex, multi-agency investigations, Peck’s story demonstrates how innovative thinking can reshape federal prosecution. Her group’s commitment to blockchain intelligence has not only strengthened the DOJ’s approach to crypto crime but has also paved the way for a new generation of prosecutors equipped to face a digital-first future. “In this line of work, you can never stop learning,” she said. “And that’s exactly what makes it so exciting.”