Submitted:
17 July 2025
Posted:
19 July 2025
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Abstract
Keywords:
1. Introduction
2. Literature Review and Hypothesis Development
2.1. Evolution of Money Laundering Detection Techniques
2.2. Graph-Based Forensic Approaches in Financial Forensics: Advances and Challenges
2.3. Transformers and Temporal Analysis in AML: Capabilities and Limitations
- Capturing long-range transaction dependencies using self-attention mechanisms was performed experimentally.
- Detection of sequential laundering patterns, such as layering, is performed more efficiently.
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TimeGAN enables robust training in the presence of scarce labelled data.Critical Limitations:
- The relationship between financial entities cannot be modelled.
- Network-based laundering patterns were ignored.
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Cross-jurisdictional schemes have not been effectively addressed.Emerging Solutions:
- Transformers hybridised with graph-based frameworks form a new structure.
- Combining sequence and relationship modelling leads to temporal graph networks.
- The entity and time dimensions must be incorporated into attention mechanisms.
2.4. Hybrid Models and Explainability
- Compared with single-modality approaches, ST-GNN architectures show an improvement of up to 22% in detecting complex laundering patterns.
- The integration of time and space facilitates the detection of intricate, cross-border schemes.
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Later typologies of laundering are more easily incorporated into adaptive learning capabilities.Critical Challenges in Explainability:
- Post hoc explanation methods have not met judicial standards of evidence
- Acceptance of these methods differs widely from one jurisdiction to another.
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Performance vs. explains that the trade-off, especially in terms of the cost-benefit, is poorly estimated.Innovative solutions
- Post-hoc application, rather than as applied during the explanation integration phase, should be changed in explainability mechanisms to improve innovation policies.
- Customisation of explanation frameworks for specific regions is a smart idea.
- Explainable AI in AML requires the development of standardised validation protocols for appropriate policies.
2.5. Research Gaps and Hypothesis
- Temporal-Relational Disconnect: No model simultaneously analyses transactional sequences (transformers) and entity networks (GNNs) for Southern Africa money-laundering topologies.
- Explainability-Scalability Trade-off: Prior hybrids sacrifice either performance (AUC<0.90) or interpretability (SHAP adoption <50%).
- Regulatory Misalignment: GDPR/FATF compliance is rarely tested in the real world (FIC, 2023).
2.6. Hypothesis
3. Materials and Methods
4. Results
4.1. Model Performance Against Traditional AML Methods (RQ1, Objective 1)
- South Africa FIC: 850,000 Currency Transaction Reports (CTRs) from 2020-2023 (Publicly available via South Africa’s FIC Annual Reports)
- Zimbabwe RBZ: 620,000 Suspicious Transaction Reports (STRs) from 2019-2023 (Aggregate data available via RBZ Supervision Reports)
- Ethereum Blockchain: 330,000 high-value transactions (greater than $10,000) from 2022-2023 (acquired via Etherscan API).
| Method | Accuracy (95% CI) | False Positive Rate | AUC-ROC |
|---|---|---|---|
| FALCON (Ours) | 98.7% (98.2–99.1%) | 1.20% | 0.992 |
| Random Forest | 72.1% (70.5–73.7%) | 8.70% | 0.812 |
| Human Auditors | 64.5% (62.8–66.2%) | 15.30% | 0.701 |
| LSTM-only Baseline | 83.4% (81.9–84.9%) | 4.90% | 0.887 |
4.2. Explainability and FAFT Compliance (RQ 2, Objective 2)
4.3. Cross-Border Detection Capability (RQ 3, Objective 3)
4.4. GDPR Compliance and Operational Feasibility (RQ4, Objective 4)
5. Discussion
5.1. Discussions Concerning the Research Questions and Goals
FALCON’s Validation
5.2. Integration with Literature
5.3. Theoretical, Practical, and Policy Implementation
5.4. Strengths and Limitations
5.5. Unexpected Findings and Alternative Explanations
5.6. Future Research Directions
6. Conclusion
Final Take-Home Message
Author Contributions
Funding
Data availability statement
Conflicts of Interest
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| Company | A1 | A2 | A3 | A4 | B1 | B2 | B3 | C1 | C2 | D1 | D2 | E1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| A1 | 1.00 | 0.87 | 0.23 | 0.45 | 0.12 | 0.34 | 0.78 | 0.56 | 0.29 | 0.41 | 0.67 | 0.38 |
| A2 | 0.87 | 1.00 | 0.19 | 0.52 | 0.08 | 0.41 | 0.83 | 0.62 | 0.35 | 0.47 | 0.73 | 0.44 |
| A3 | 0.23 | 0.19 | 1.00 | 0.76 | 0.89 | 0.15 | 0.32 | 0.28 | 0.71 | 0.54 | 0.26 | 0.63 |
| A4 | 0.45 | 0.52 | 0.76 | 1.00 | 0.68 | 0.39 | 0.47 | 0.51 | 0.84 | 0.72 | 0.33 | 0.58 |
| B1 | 0.12 | 0.08 | 0.89 | 0.68 | 1.00 | 0.25 | 0.14 | 0.37 | 0.79 | 0.65 | 0.18 | 0.82 |
| B2 | 0.34 | 0.41 | 0.15 | 0.39 | 0.25 | 1.00 | 0.69 | 0.85 | 0.42 | 0.31 | 0.76 | 0.27 |
| B3 | 0.78 | 0.83 | 0.32 | 0.47 | 0.14 | 0.69 | 1.00 | 0.74 | 0.38 | 0.53 | 0.91 | 0.46 |
| C1 | 0.56 | 0.62 | 0.28 | 0.51 | 0.37 | 0.85 | 0.74 | 1.00 | 0.49 | 0.36 | 0.88 | 0.35 |
| C2 | 0.29 | 0.35 | 0.71 | 0.84 | 0.79 | 0.42 | 0.38 | 0.49 | 1.00 | 0.77 | 0.31 | 0.69 |
| D1 | 0.41 | 0.47 | 0.54 | 0.72 | 0.65 | 0.31 | 0.53 | 0.36 | 0.77 | 1.00 | 0.44 | 0.86 |
| D2 | 0.67 | 0.73 | 0.26 | 0.33 | 0.18 | 0.76 | 0.91 | 0.88 | 0.31 | 0.44 | 1.00 | 0.39 |
| E1 | 0.38 | 0.44 | 0.63 | 0.58 | 0.82 | 0.27 | 0.46 | 0.35 | 0.69 | 0.86 | 0.39 | 1.00 |
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