Every Contact Leaves a Trace: Why Financial Trails are the New Fingerprints

When used effectively, following the money solves crimes and dismantles the networks behind them.
Aug. 7, 2025
6 min read

What to Know

  • Financial evidence connects suspects to crimes with precision, showing who benefited, how the scheme worked and where the proceeds went. 
  • This evidence often never makes it to a courtroom due to the overwhelming volume and complexity of the information. 
  • In May, 10 people were sentenced to federal prison for their roles in a multistate, black-market marijuana and money laundering ring—an outcome made possible by financial evidence. 
  • For every successful case, countless others stall out because investigators face hurdles in translating financial data into actionable evidence. 

By David Tyree, Senior Advisor for Financial Crime Detection and Anti-Money Laundering at Valid8 Financial

A money trail can break an investigation wide open and expose a massive criminal operation. Like a fingerprint, financial evidence connects suspects to crimes with precision, showing who benefited, how the scheme worked and where the proceeds went. But often, this evidence never makes it to a courtroom. Why? It’s not a lack of data. Quite the opposite: It’s the overwhelming volume and complexity of the information. 

Fingerprinting has become second nature to law enforcement, while financial analysis is still seen as specialized. But using financial evidence can deliver a deeper blow to criminals. When used effectively, following the money solves crimes and dismantles the networks behind them.

In May, 10 people were sentenced to federal prison for their roles in a multistate, black-market marijuana and money laundering ring—an outcome made possible by financial evidence. The investigation took off after investigators found one suspect carrying $50,000 in cash. Tracing the money led agents to uncover the broader network, identify co-conspirators and seize $400,000 in cash and $4.7 million in real estate, essentially defunding the operation. 

Unfortunately, this outcome is the exception. For every case like this, countless others stall out because investigators face hurdles in translating financial data into actionable evidence. These limitations leave the infrastructure of criminal enterprises untouched, allowing them to continue operating even after arrests. To make a long-term impact on crime, financial evidence must become a standard part of policing. 

Why financial investigations stall

Following the money is complex and arduous. Law enforcement officers must manage time constraints, massive volumes of data, complex transactional patterns and strict legal boundaries. 

These investigators are trained to kick down doors and collect physical evidence, not make sense of spreadsheets filled with thousands of transactions. You wouldn’t send a forensic accountant to a crime scene without proper training, so why should police officers and detectives be expected to decode a sea of numbers without support and guidance? Investigators often become overwhelmed by financial data and default to the tools they know.

The volume of evidence in a financial investigation is enormous. Investigators must collect and review years of documents from dozens of institutions, including bank statements, check and deposit slip images, peer-to-peer payment histories, brokerage accounts and cryptocurrency exchanges. The data quantity quickly becomes unwieldy. For example, a single Suspicious Activity Report (SAR) can generate thousands of pages of supporting records. Once, I had to buy a standalone computer solely to manage data for one report.

Investigators must sort, enter, verify and reconcile all of the transactions, which alone can take weeks. Then, they must uncover transactions that could signal illegal activity. Criminals use sophisticated tactics to obscure and protect their money, often mirroring legitimate financial activities to blend in. It’s not a needle in a haystack; it’s a needle in a needle stack. Most investigators—especially at the state and local level—lack the training to identify complex, layered money trails. Instead, they are left staring at pages of data with no idea where to start.

Communication barriers can make things worse. Law enforcement speaks in different terms than financial institutions, which often means evidence gets lost in translation. For example, investigators may overlook important transactions because they are obscured by compliance jargon, or financial institutions may be unable to fulfill document requests that don’t align with internal reporting protocols.

Similar disconnects happen internally. Investigators can struggle to explain complex financial patterns to supervisors, analysts or prosecutors. Without a shared language or framework, cases stall, not because the evidence is weak but because no one knows how to communicate it.

Even if they do uncover a “smoking gun” amid the spreadsheets, many investigators hesitate to follow the lead. The legal boundaries surrounding financial documents are complex, and no one wants to risk compromising a case. For example, you can’t mention a SAR in court, reference it in a warrant or use it to explain probable cause. While there are legal ways to build a case around a SAR, most investigators haven’t received the necessary guidance. That uncertainty leads to inaction. 

No one expects officers to become forensic accountants. What we need are practical tools and training that empower all levels of law enforcement to follow the evidence without getting lost in it.

Financial evidence is the new fingerprint

Most law enforcement officers see financial evidence as valuable but intimidating, overly technical and outside the scope of their day-to-day training. But that was once true of other tools, too. Fingerprinting used to require a specialist, but training and technology have made this investigative tool accessible for virtually any case. We can do the same for financial evidence. 

The first step in making financial evidence easier to use is improving how the data gets processed and prepared. Verified financial intelligence (VFI) platforms automate these tasks, turning thousands of documents into a comprehensive dataset in a few hours rather than weeks, a game-changer for resource-strapped local agencies. When investigators enter data manually, it’s easy to miss transactions, mislabel entries or overlook patterns. VFI tools automatically extract, clean, and organize thousands of records more accurately and efficiently than a human can. The technology delivers a comprehensive, defensible, admissible dataset that investigators and prosecutors can rely on.

However, a high-quality dataset means little without the ability to interpret it. Investigators don’t have time to comb through the spreadsheets line by line and can’t possibly learn every technique criminals use to hide money. They need a tool to flag anomalies, surface connections and visualize cash flow so they can spot leads without being a financial expert. VFI solutions map criminal networks and present evidence in a standardized, easy-to-interpret output. 

But tools alone aren’t enough. Investigators also need instructions on what to do with the information. Scenario-based training that mirrors real cases helps officers build instincts and ask better questions. Officers must also learn how to preserve evidence integrity and explain financial findings to colleagues, prosecutors, judges and juries. With the right guidance, what once felt intimidating becomes routine.

Financial evidence is not bonus corroboration—it is the concrete evidence necessary to thwart criminal enterprises. With the right tools and training, law enforcement can solve more cases, convict more criminals and dismantle the infrastructure fueling crime to build safer communities. We must equip every investigator to follow the money. ​​

About the Author

David Tyree is a 25-year veteran of the U.S. Drug Enforcement Administration and a recognized expert in financial crime investigations, anti-money laundering, and asset forfeiture. Throughout his career, he led high-impact cases resulting in over $80 million in seized criminal assets tied to drug trafficking, human trafficking, and transnational organized crime.

Now serving as Senior Advisor for Financial Crime Detection and Anti-Money Laundering at Valid8 Financial, David helps law enforcement agencies understand how to use technology to convert complex financial data, spanning from bank statements to Bitcoin, into clear, courtroom-ready narratives. He is certified by the Association of Certified Anti-Money Laundering Specialists (ACAMS) and has held investigative posts across the U.S. and abroad, including in Portugal and Cape Verde.

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