A client receives €40,000 in USDT in his wallet, intends to exchange it for Bitcoin, and withdraw it via an exchange. Shortly thereafter, the accusation arises: the coins originated from an investment fraud, and the client is accused of money laundering. At precisely this point, a crypto case hinges not solely on the legal text, but on whether the criminal origin of the coins can be forensically proven or refuted.
Finanz Forensik GmbH is a forensic financial investigation service provider specializing in blockchain analysis. We prepare court-admissible reports on the origin and movement of crypto assets for defense attorneys, representatives of victims, and compliance departments.
This article connects the criminal law framework of the money laundering provision following the comprehensive crime reform with the forensic practice of Tint analysis. You will learn what the FIFO, Last-in-first-out, Pro-Rata and Poison models reveal about the contamination of coins and where their vulnerabilities lie.
The most important information at a glance
- Pre-offense principle Since the 2021 reform, any criminal offense can be considered a predicate offense for money laundering. The list of predicate offenses has been abolished, and the scope of application has been massively expanded.
- Crypto as the object of the crime: Bitcoin, stablecoins and others Token These are suitable objects for money laundering. What matters is the tainted origin, not the legal status of the coin.
- Carelessness is enough: Even those who grossly negligently fail to recognize the criminal origin of the funds are committing a crime. Money mules and unsuspecting recipients quickly come under scrutiny.
- Taint models: FIFO, LIFO, Pro-Rata and Poison categorize tainted and legitimate coins differently and deliver different results with identical data.
- Federal Court of Justice (BGH) line: The mere possession of fraudulent proceeds does not constitute money laundering. Only independent steps to conceal the proceeds justify the accusation.
- Two perspectives: The plaintiff must prove the origin of the evidence; the defense challenges Taint's assumptions. Both sides need reliable forensic evidence.
Section 261 of the German Criminal Code after the comprehensive crime reform: The predicate offense principle
With the Act to Improve the Criminal Prosecution of Money Laundering of March 18, 2021, the legislature fundamentally restructured the definition of money laundering. Until then, money laundering was only punishable if the proceeds originated from one of the predicate offenses listed in the catalog. This catalog has been abolished. Since then, the so-called "all-crime" approach has applied: any unlawful act can constitute a predicate offense for money laundering, from investment fraud and extortion to drug trafficking.
This is significant for cryptocurrency matters. Anyone who receives, exchanges, or withdraws coins can be prosecuted as soon as any crime is involved at the beginning of the chain. The penalty for intentional money laundering ranges up to five years imprisonment or a fine. In particularly serious cases, such as commercial or organized crime, sentences of six months to ten years are possible.
The predicate offense principle shifts the focus of the proceedings to a question of fact: Can the tainted origin of the specific coin be proven? Unlike cash, every transfer of crypto assets is publicly documented on the blockchain. This opens up possibilities for proof that never existed with the traditional cash system, but requires precise technical attribution.
It is also important to note the principle of predicate punishment. Someone already convicted of a predicate offense, such as fraud, should not be additionally punished for money laundering for the same offense. Separate criminal liability only arises when independent actions beyond the predicate offense are involved. This distinction is frequently disputed in the crypto context and can only be clarified by examining the specific transaction steps.
Elements of the offense and object of the offense: Why coins are suitable objects for money laundering
The core elements of this offense are concealing an object, disguising its origin, and acquiring, possessing, or using it for oneself or a third party. In the case of cryptocurrencies, a whole range of everyday processes fulfill these criteria: forwarding to a new wallet, exchanging Bitcoin for a stablecoin, routing through a decentralized exchange, or concealing the object via a mixed service.
Cryptocurrencies are suitable objects of crime. The decisive factor is not whether a token is classified as a unit of account, a financial instrument, or simply a data record, but whether it can be traced back to a predicate offense. Authorities also investigate surrogates: if a tainted coin is exchanged, the exchanged asset can perpetuate the contamination. This is precisely where the forensic question of contamination comes into play.
The path of coins can be reconstructed using blockchain analysis and address clustering methods. Heuristic procedures group addresses into economic units, revealing which wallet received, held, and forwarded a given amount. This forms the basis for any reliable statement of origin.
Intent and recklessness: The underestimated trap
The basic offense requires intent. The perpetrator must at least consider the tainted origin possible and accept it as a likely consequence. In addition, there is the offense of negligent money laundering, which carries a penalty of up to two years' imprisonment or a fine. A person acts negligently if, given the circumstances, the criminal origin should have been obvious to them and if they fail to recognize it due to gross negligence or particular indifference.
This second scenario is the real trap. So-called money mules, who make their accounts or wallets available for a supposed side job, are regularly prosecuted for negligent money laundering. However, the law requires concrete suspicions for such an accusation, not just abstract warning signs. Whether unusually large sums, anonymous clients, and opaque processes are sufficient in a given case is a matter of overall assessment.
This provides a point of leverage for the defense: if the origin of the coins was not immediately obvious, for example, because they were acquired through a regulated exchange with Know Your Customer (KYC) verification, then the element of recklessness is lacking. Conversely, for the plaintiffs, the circumstances giving rise to suspicion must be concretely and comprehensibly substantiated.
Taint analysis: How forensics calculates the contamination of coins
Taint analysis examines the extent to which a wallet or coin is linked to criminal activity. Since transactions involve multiple inputs and outputs, an attribution model is needed to determine what proportion of an output is considered tainted. Four models have become established, and they regularly produce different results with the same data.
FIFO: First-in-first-out
The FIFO model assumes that coins received first are also spent first. Money flows are thus arranged in a chronologically traceable order. FIFO is lossless, meaning that a tainted amount can be traced forwards to its current location and backwards to its origin. In many legal and tax systems, FIFO is considered the obvious standard because it provides a clear, deterministic rule.
LIFO: Last-in-first-out
LIFO reverses the order: coins received most recently are considered spent first. This model can lead to significantly different attributions than FIFO, especially if a wallet accumulates both legitimate and fraudulent inflows over an extended period. LIFO is less common in everyday forensic work, but it serves as a useful check to reveal the sensitivity of a result to the chosen ordering rule.
Pro-rata and haircut: proportional allocation
The pro-rata or haircut model distributes the taint proportionally. If a wallet consists of 50 percent tainted funds, each output is considered 50 percent tainted. Each output thus receives a share of the taint corresponding to its proportion of the total amount. While the model appears fair, it dilutes the taint with each transaction, so that after many transactions, only small percentages remain.
Poison: complete contamination
The Poison model is the most stringent. As soon as a single incriminated person... Satoshi If Poison enters a wallet, the entire balance is considered contaminated, even seemingly harmless funds. Poison thus significantly exaggerates the extent of the contamination and leads to far-reaching chains of suspicion. It is hardly sufficient on its own to prove a crime, but it can point to investigative avenues. In practice, it is primarily suitable as an initial filter to narrow down suspicious addresses, not as the basis for a reliable determination of origin.
What the models really reveal about contamination
No model is objectively correct. FIFO and LIFO are ordering decisions, pro-rata is a distribution assumption, and poison is a maximum hypothesis. Which model is applied can drastically alter the result: The same coin might be considered 100% contaminated according to poison, only a few% according to pro-rata, and not at all according to FIFO. A forensic report must therefore disclose and justify the choice of model.
It becomes particularly challenging when Crypto Mixer and interposed mixing services. They deliberately disrupt the direct mapping of inputs and outputs. Depending on the model, this results either in a widely dispersed, diluted taint distribution or an excessive contamination of all downstream addresses. Both extremes are not very meaningful on their own.
Attribution data provides additional clarity. If an exit leads to a known criminal infrastructure, such as addresses associated with underground marketplaces like the... Huione Group, This supports the statement about origin regardless of the calculated taint. Good forensics combines the model calculation with such attributions and objectively interprets the result, instead of absolutizing a single percentage value.
Federal Court of Justice (BGH) ruling: Distinction between fraud and money laundering
The Federal Court of Justice draws a clear line between participation in the predicate offense and independent money laundering. Anyone who launders fraud proceeds in cryptocurrency Simply acquiring and holding money does not in itself constitute money laundering. Only separate, independent steps, distinct in time and substance, justify the accusation, such as transferring funds to third-party wallets, exchanging them for other coins to conceal their origin, or converting them into surrogates.
Self-laundering is also a criminal offense since the reform. The perpetrator of the predicate offense can additionally be prosecuted for money laundering if, after the enrichment has been completed, they undertake independent acts of concealment. According to case law, the internal distribution of the proceeds, simply depositing them into one's own accounts without additional concealment, or passing them on to accomplices do not automatically constitute the offense.
In practical terms, this means that the question of sentencing often hinges on whether the accused is responsible for the original offense or only for the subsequent money laundering. For both sides, the forensic reconstruction of the transaction steps is therefore not a technical detail, but the core of the legal assessment.
Perspective of the private prosecution: proving the tainted origin
From the perspective of the victims and their representatives, the goal is to provide conclusive proof of the coins' origin from the predicate offense. A report admissible in court regarding this matter is required. Crypto forensics The report traces the path from the time of the crime to the destination address, names the taint model used, and documents each assignment in such a way that it can withstand scrutiny in court proceedings.
A conservative approach is crucial. Relying solely on the Poison model risks having the defense expose its exaggeration. A more convincing strategy is to run multiple models in parallel and to strongly demonstrate the origin of the data where all models agree. Supplemented by attribution data and timestamps, this creates a chain of evidence that can withstand critical scrutiny.
We offer specialized support to investigative authorities and public prosecutors, from securing on-chain evidence to preparing it clearly for trial. Especially with international chains operating across multiple exchanges and networks, proof depends on meticulous technical work.
Defense perspective: attack the Taint assumptions
The defense focuses precisely on the weaknesses of the models. The strongest leverage lies in the choice of model itself: If the contamination was calculated according to Poison, it can be shown that FIFO or pro-rata methods do not capture the specific coin at all, or only to a fraction of its extent. Even proof that the result depends entirely on an arbitrary assumption of order can undermine the evidence.
Other approaches include unreliable clustering heuristics that incorrectly group addresses into a single unit, missing or outdated attribution data, and breaks in the chain caused by mixers or cross-chain bridges. The subjective element also remains crucial: Could the client even determine the origin if forensic analysis only yields a result after extensive research?
A forensic counter-report systematically organizes these points and examines whether the prosecution's evidence is methodologically sound. For defense attorneys, we identify the critical points and present them in a robust manner. Our page on forensic support for lawyers explains the details of how this collaboration works.
Prove or disprove crypto money laundering: Talk to us
Whether you want to prove the origin of tainted coins or challenge a taint allegation in the prosecution's case: The outcome of a cryptocurrency-related money laundering investigation depends on the quality of the forensic analysis. We deliver court-admissible, GDPR-compliant reports, nationwide and discreetly, and will get back to you within one business day.
Call us at +49 6057 772 994 86 or write to postfach@finanz-forensik.de. You can also submit your inquiry directly via our contact form. We will review your case and tell you openly what the blockchain data reveals.
Further articles on this topic: Blockchain analysis and clustering, For prosecutors as well as For lawyers.
Note: This article is for general information purposes only and does not replace legal advice in individual cases. Finanz Forensik GmbH is a forensic service provider and not a law firm.
FAQ: Money laundering with cryptocurrency
Yes. Cryptocurrencies like Bitcoin or stablecoins are suitable for money laundering. Anyone who conceals coins, disguises their origin, or acquires, holds, or uses them even though they originate from a crime is committing a crime. The penalty can be up to five years imprisonment, and up to ten years in particularly serious cases.
Until 2021, money laundering was only punishable in the case of specific predicate offenses. Since the law of March 18, 2021, any unlawful act can constitute a predicate offense. This has significantly broadened the scope of application. In the case of cryptocurrencies, this means that even a single offense at the beginning of the transaction chain can trigger criminal liability.
No. According to the German Federal Court of Justice (BGH), the mere possession of fraudulent proceeds does not constitute money laundering. Only independent, temporally separate steps of concealment, such as exchanging the funds for other coins or transferring them to third-party wallets, justify the charge. This distinction often determines the applicable penalty.
Taint analysis examines the extent to which a coin or wallet is linked to criminal activity. Since transactions involve multiple inputs and outputs, a model assigns the taint to the outputs. The result forms the basis for statements about the origin of a cryptocurrency amount.
FIFO prioritizes receiving coins over receiving them, while LIFO reverses this order. Pro-rata distribution of the taint is proportional, diluting it with each hop. Poison treats the entire holding as contaminated as soon as a contaminated amount is received. The same data can lead to very different results depending on the model.
No model is objectively correct. FIFO and LIFO are ordering rules, pro-rata is a distribution assumption, and poison is a maximum hypothesis. A reputable forensic report discloses the model choice, justifies it, and ideally runs several models in parallel to demonstrate the robustness of the result.
Yes. Negligent money laundering is punishable by up to two years in prison. Negligent laundering is defined as acting with obvious recognizability of the criminal origin of the money and gross negligence in failing to recognize it. This often affects financial agents. Concrete suspicions are required, not merely abstract warning signs.
The defense focuses on the choice of model, demonstrating that another model either fails to capture the coin entirely or only partially. Further arguments include unreliable clustering heuristics, outdated attribution data, and chain breaks caused by mixers or bridges. The crucial question is also whether the accused could even identify the coin's origin.
Mixers deliberately disrupt the direct correlation between inputs and outputs, complicating analysis. Depending on the model, this results in either a broadly diluted or an excessive contamination. On their own, neither is very informative. A reliable determination of origin only emerges when combined with attribution data and timestamps.
As early as possible, ideally as soon as the allegation arises and even before any statements or motions have been finalized. Only an early analysis can reveal whether the origin of the coins can be reliably proven or refuted. We will review your case nationwide and discreetly. Call us at +49 6057 772 994 86 or email us at postfach@finanz-forensik.de.
