Efficiency of Cooperation Between Various Services and Specialists in the Investigation of Terrorist Murders: Development of an Optimized Algorithm

Ihor Demidov¹ , Arzu Hadzhiieva², Ivan Tkachov³, Oleksandr Kozenko³ and Denys Bohdan⁴
1. Interregional Academy of Personnel Management, Kyiv, Ukraine
2. Faculty of Philosophy, School of Political and Social Sciences, Western Caspian University, Baku, Azerbaijan
3. Scientific Laboratory of National Academy of the Security Service of Ukraine, Kyiv, Ukraine
4. Antiterrorist Centre at the Security Service of Ukraine, Kyiv, Ukraine
Correspondence to: Ihor Demidov, Demidov_ihor1@gmail.com

DOI: https://doi.org/10.70389/PJS.100240

Additional information

• Ethical approval: N/a
• Consent: N/a
• Funding: No industry funding
• Conflicts of interest: N/a
• Author contribution: Ihor Demidov, Arzu Hadzhiieva, Ivan Tkachov, Oleksandr Kozenko and Denys Bohdan – Conceptualization, Writing – original draft, review and editing
• Guarantor: Ihor Demidov
• Provenance and peer-review: Unsolicited and externally peer-reviewed
• Data availability statement: N/a

Keywords: Interagency cooperation models, Terrorist homicide investigations, Algorithmic optimization, Procedural complexity reduction, Cross-jurisdictional coordination.

Peer Review
Received: 27 October 2025
Last revised: 6 November 2025
Accepted: 17 December 2025
Version accepted: 2
Published: 31 January 2026

Plain Language Summary Infographic

Highlights

• Terrorist attacks remain among the most destructive global security threats.
• Analysis showed that effectiveness in terrorist homicide investigations depended on formalized interagency cooperation.
• Effective investigation of terrorist homicides depends on formalized, legally regulated, and institutionally structured interagency cooperation.
• The resulting optimized algorithm reduced operational complexity by 20%.
• The study’s novelty lies in formalizing typologies of procedural-legal cooperation mechanisms.

Introduction

Terrorist attacks remain among the most destructive global security threats, undermining national stability and international law.^1,2 Terrorist-motivated homicides pose acute risks, causing mass casualties and demanding rapid, coordinated responses.^3,4 Their investigation involves multiple actors-law enforcement, intelligence, forensics, prosecutors, and international partners.^5,6 However, interagency practices vary from integrated hierarchies to fragmented or politicized systems,^7–10 underscoring the need for comprehensive analysis and a unified adaptable cooperation algorithm. The aim of this study is to identify, arrange, and optimize procedural and legal mechanisms of cooperation between different services and specialists in the investigation of terrorist murders. The aim involves the fulfilment of the following research objectives:

• Analyse the practices of cooperation between services in the investigation of terrorist murders;
• Classify models by effectiveness;
• Identify typical features of cooperation structures;
• Create and optimize an interaction algorithm;
• Compare algorithms according to qualitative and quantitative criteria;
• Evaluate the effectiveness of optimization.

Research question: How can structural interagency cooperation mechanisms be optimized to reduce procedural complexity and enhance operational efficiency in investigations of terrorist-motivated murders?

Research hypothesis: The optimization of cooperation algorithms–based on structural integration, legal synchronization, and procedural streamlining– significantly improves coordination efficiency and response capabilities in investigations of terrorist-motivated murders.

The current studies on the effective cooperation between different services and specialists in the investigation of terrorist murders are reviewed below.

Marzuki et al. identified insufficient coordination between regional police and specialized units in South Sumatra.¹¹ Counterterrorism intelligence remained centralized in Densus 88, with minimal regional police participation. Kibe and Ngari identified lagging interagency responses to evolving terrorist tactics in Kenya since 1998.¹² They stressed the need for permanent counterterrorism units, stronger coordination, technological modernization, and expanded international cooperation. Norris found police-targeted killings more often driven by mental disorders and radical ideologies than activism.¹³ This highlighted the need for coordinated action among police, intelligence, and psychiatric services. Hariyanto et al. emphasized the key role of the state and the NII Crisis Center in countering religious radicalism.¹⁴ They highlighted the need for systematic cooperation between government agencies and civil society to prevent extremist threats, including youth radicalization.

Guttmann demonstrated that effective prevention of 1970s terrorist attacks, such as Black September, relied on strong interagency intelligence exchange.¹⁵ Historical analysis confirmed that coordinated information sharing was critical for identifying tactics and averting attacks. Zhao et al. confirmed the effectiveness of international counterterrorism cooperation within the Shanghai Cooperation Organization.¹⁶ Their findings showed reduced attacks and casualties, emphasizing the importance of coordinated, multi-level interstate mechanisms. Putri et al. demonstrated that U.S.–Nigeria military cooperation, particularly Air Force engagement, significantly enhanced Nigeria’s counterterrorism capacity against Boko Haram.¹⁷ They underscored the role of international collaboration in strengthening national security amid complex threats. Iqbal et al. found that China–Pakistan counterterrorism cooperation evolved with China’s expanding economic role and shifting regional security context.¹⁸ Beijing’s reduced reliance on Islamabad reflected growing autonomy of bilateral security mechanisms.

Adlina explained India’s post-2008 refusal to cooperate with Pakistan through prisoner’s dilemma dynamics.¹⁹ The decision stemmed from historical distrust, security perceptions, and political context, limiting bilateral counterterrorism collaboration. Cui et al. showed that terrorist groups increasingly form cooperative core–periphery networks.²⁰ Effective counteraction, they noted, requires coordinated interagency efforts to map and disrupt these structures. Current research highlighted interagency coordination as crucial in terrorist homicide investigations, revealing fragmented interaction among security, forensic, and civil actors. Simultaneously, evolving information exchange and regulatory frameworks underscored the need for a multi-level cooperation model.

Methods and Materials

Research Design

This study was conducted according to the scheme below (Figure 1).

Methods: A multi-method qualitative design was used, combining legal analysis, structural modeling, and efficiency evaluation through eight sequential stages ensuring reproducibility.

Relevant Analysis: The initial stage involved analysis of national and international regulations on interagency cooperation in terrorist homicide investigations, including domestic laws and supranational instruments. These were mapped to procedural stages and aligned with cross-border case precedents.

Development of a Generalized Algorithm: A generalized interagency cooperation algorithm was synthesized, covering detection, intelligence fusion, tasking, evidence collection, cross-jurisdictional alignment, authorization, and disposition. Each phase defined responsible agencies, procedural triggers, and communication protocols under rule-of-law alignment.

Development of an Optimized Algorithm: The model was optimized by removing redundancies, enhancing coordination at key interfaces, and adding reverse-audit loops for legal compliance. Adjustments improved operational speed, reduced legal ambiguity, and integrated international partners early.

Structural Qualitative Comparative Analysis: Generalized and optimized algorithms were compared across six dimensions legal coherence, transparency, responsiveness, adaptability, accountability, and rights protection using a five-level qualitative scale with discourse-based assessment of strengths and gaps.

Structural Element Comparative Analysis: Quantitative analysis showed a reduction of procedural units from 212 to 170 (≈20%), confirming lower complexity. Control points and feedback loops indicated higher operational controllability.

Determining Efficiency: Efficiency was measured by time compression, interaction coherence, and cross-jurisdictional adaptability. Normative modeling and simulations inferred performance gains despite limited field testing.

Sample: The sample comprised 25 states and international organizations selected by purposive criteria: legal-system diversity (common, civil, hybrid), regulatory maturity in interagency counterterrorism, and availability of verified case data. Analysis covered statutory bases, cooperation protocols, and investigation algorithms. Limitations concerned transparency and cross-jurisdictional generalizability. A detailed description of the sample is provided in Appendix B.

Instruments: A structured instrument based on a conditional operational complexity model was utilized for comparative evaluation of interagency algorithms in terrorist homicide investigations. It integrated process analysis, communication load metrics, and matrix-based efficiency assessment. Expert modeling and quantitative mapping ensured validity, though replication required disaggregated procedural data and expert input.

Stage complexity assessment: (1)

where S_i – complexity of the i th stage; A_i – the number of active subjects (agents, bodies, structures); V_i – the number of inter-agent interactions (paired connections between subjects that involve information or procedural exchange); C_i – the procedural complexity coefficient (1 – low, 2 – medium, 3 – high).

Overall complexity of the algorithm: (2)

where n – number of stages in the algorithm. A detailed description and example of the calculation is provided in Appendix A.

Results

Applying the established methodology of this study, a relevant analysis of the current experience of cooperation between various services and specialists in investigating terrorist murders (including legal norms and known investigation cases) will be conducted for 25 leading countries and international organizations (Table 1).

Table 1: Results of the relevant analysis.
Country/Organization	Interaction Algorithm	Legal Norms	Known Investigation Cases
USA	FBI–DHS–ATF–CIA coordination via JTTF	Patriot Act, FISA	9/11, Boston Marathon (2013)
UK	MI5–Counter Terrorism Command–CPS	Terrorism Act 2000	London Bombings (2005)
France	DGSI– gendarmerie–national police	Code de la sécurité intérieure	Bataclan Attack (2015)
Germany	BfV–BKA–Länder Police	Grundgesetz, BKA-Gesetz	Berlin Truck Attack (2016)
Italy	DIGOS–Carabinieri–Polizia di Stato	Codice Penale, D.Lgs. 159/2011	Milan Shooting (2016)
Canada	RCMP–CSIS–Integrated Security Units	Anti-Terrorism Act, CSIS Act	Toronto Van Attack (2018)
Spain	Guardia Civil–CNI–Policía Nacional	Ley de Enjuiciamiento Criminal	Madrid Bombings (2004)
Australia	ASIO–AFP–State Police	ASIO Act 1979	Sydney Siege (2014)
Israel	Shin Bet–IDF–Israel Police	Counter-Terrorism Law (2016)	Sbarro bombing (2001)
Turkey	MIT–Turkish National Police–Jandarma	Law No. 3713	Reina nightclub attack (2017)
India	NIA–RAW–CBI–State Police	UAPA, NIA Act	Mumbai Attacks (2008)
Indonesia	Densus 88–BNPT–Polri	UU Terorisme 5/2018	Surabaya bombings (2018)
Kenya	APS–NSIS–CID	Prevention of Terrorism Act 2012	Westgate Mall (2013)
Nigeria	DSS–NAF–NIA	Terrorism Prevention Act (2011)	Abuja UN bombing (2011)
Pakistan	ISI–CTD–FIA	Anti-Terrorism Act 1997	Peshawar School Attack (2014)
Ukraine	SBU–National Police–Prosecutor General’s Office	Criminal Code of Ukraine, Law on Security Service of Ukraine	MH17, Kharkiv (2022)
Poland	ABW–Police–Prokuratura	Kodeks Karny, Ustawa o ABW	Warsaw bomber plot (2019)
Sweden	Säpo–Polisen–Försvarsmakten	Terrorism Act (2017:630)	Stockholm Truck Attack (2017)
Japan	NPA–PSIA–MOJ	Act on Punishment of Financing Terrorism	Tokyo Subway Sarin Attack (1995)
South Korea	NIS–KNP–Supreme Prosecutors’ Office	Counter-Terrorism Act (2016)	Seoul Subway Plot (2005)
European Union	EUROPOL–Eurojust–Frontex	Directive (EU) 2017/541	Paris–Brussels Network (2015–2016)
INTERPOL	Global database, I-24/7 channels	Constitution of INTERPOL, RPF	Global I-24/7 alerts
UN	UNODC–CTED– Human rights mechanisms	UN Charter, UNSC Res. 1373	Sri Lanka (2019), CTED reviews
NATO	CJTF–Allied Command Operations	North Atlantic Treaty, STANAGs	Afghanistan missions (post-2001)
SCO	RATS– national security services	SCO Charter, RATS Agreement	Xinjiang-related operations
Source: Developed by the authors.

Analysis (Table 1) showed that effectiveness in terrorist homicide investigations depended on formalized interagency cooperation, legal regulation, and operational response. Leading jurisdictions confirmed the importance of algorithmic clarity, unified legal frameworks, and international coordination. This informed the generalized cooperation algorithm (Table 2).

Table 2: Generalized algorithm.
Algorithm Steps	Procedural Activities
1. Rapid detection and initial response	Secure the scene and evacuate victims Collect primary evidence and data Transfer information to the coordination center
2. Formation of an interagency investigation team	Form a joint operational team (e.g., JTTF) Appoint an investigation coordinator Define agency responsibilities
3. Analysis and exchange of intelligence data	Check suspects in national and international databases Assess terrorist links Use IT platforms to analyze communications, movements, and transactions
4. Forensic and criminalistic support	Examine bodies and identify victims Analyze explosion, DNA, and weapon traces Provide forensic conclusions on cause and mechanism of death
5. International coordination (if needed)	Request international legal assistance Exchange data via I-24/7 or similar systems Coordinate with foreign authorities to uncover terrorist networks
6. Legal qualification and procedural registration	Provide legal assessment of suspects’ actions Formulate charges under national law Initiate pre-trial investigation and procedural support
7. Institutional reporting and analytics	Prepare analytical report on agency performance Identify coordination gaps Propose improvements to the response system
8. Public communication	Provide verified public information Prevent panic and sustain public trust Communicate security measures
Source: Developed by the authors.

The algorithm (Table 2) integrated best practices of high-cooperation states, ensuring procedural coordination in terrorist homicide investigations, and was later optimized using international experience (Table 3).

Table 3: Optimized algorithm.
Algorithm Steps	Procedural Measures
1. Activation of response and assessment of the situation	Arrive promptly and secure the scene Provide medical aid Record initial evidence Notify the coordination center immediately
2. Activation of the inter-agency coordination mechanism	Form interagency investigation team Appoint coordinator Assign operational, analytical, and prosecutorial roles
3. Intelligence data sharing and analytical support	Collect and integrate national and international data Analyze threats and terrorist links Coordinate with INTERPOL, EUROPOL, and others
4. Forensic support	Conducted forensic examinations; identified victims Determined weapon type and crime mechanism Compiled and preserved the evidentiary base
5. Legal qualification and pre-trial investigation	Determine crime qualification (terrorism, premeditated murder, etc.) Register criminal proceedings Conduct investigative actions and arrests
6. International legal assistance (as needed)	Send requests and exchange evidence Use mutual legal assistance channels Join joint investigation teams (JITs)
7. Post-operational audit and institutional training	Analyse agency performance and identify shortcomings Update tactics and train personnel Implement institutional reforms
8. Public communication and reporting	Ensure investigation transparency Prevent disinformation Inform the public and build trust
Source: Developed by the authors.

The optimized algorithm (Table 3) unified procedures, enhanced efficiency and flexibility, and enabled national and international scalability. Step-by-step qualitative comparison of generalized and optimized models (Table 4) detailed structural improvements in interagency cooperation mechanisms.

Table 4: Results of the step-by-step structural qualitative comparative analysis.
Criterion	Generalized Algorithm	Optimized Algorithm	The Impact of Optimization on the Efficiency of Algorithmization
Stage structure	Eight stages, with detailed actions of each service	Eight stages, structured and grouped according to the logic of efficiency and consistency	Reducing duplication of functions, strengthening the interconnections between response phases
Action formulation	Partially descriptive, with possible repetitions or overlaps of powers	Specified, presented according to the logic of actions “who-what-how,” with a clear functional division	Increasing the accuracy of task performance and reducing the risk of inconsistency
Role of the coordination mechanism	Present, but not centralized	The role of the interdepartmental coordinator is strengthened, as well as the incident management system	Ensuring continuity of management at all stages of the investigation
Integration of the international component	Provided only in later stages (#5)	Integrated flexibly: with the possibility of connection at any phase, depending on the cross-border aspect	Increasing efficiency in cooperation with EUROPOL, INTERPOL, UN, etc.
Institutional adaptability	The algorithm is less flexible for scaling or application in crisis conditions	Built modularly, allows adaptation to the context and legislation of the country	Increasing universality and relevance in different legal systems
Information interaction	Mentioned, but without emphasis on common platforms	Centralized analytical support, data exchange through national and international IT systems are provided	Increasing the accuracy and speed of information processing
Analysis and learning phase	Available in the form of “institutional reporting”	Transformed into a full-fledged audit with the implementation of changes and a feedback cycle	Increasing the institutional capacity for self-correction and development
Public communication	Presented as part of the crisis response	Integrated as the final phase of strategic communication and public trust management	Strengthening public support and transparency of the actions of law enforcement agencies
Source: Developed by the authors.

The optimized algorithm (Table 4) enhanced efficiency, coordination, flexibility, and institutional accountability, converting fragmented actions into a unified counterterrorism system. A structural comparative analysis of generalized and optimized cooperation models followed, based on national and international experience (Table 5).

Table 5: Results of step-by-step comparative analysis of interagency cooperation algorithms in terrorist homicide investigations.
Stage	Subjects	Interactions	Complexity	Rating
Generalized Algorithm
1	3	3	2	18
2	4	6	2	48
3	4	6	3	72
4	3	3	2	18
5	3	3	2	18
6	3	3	2	18
7	3	3	2	18
8	2	1	1	2
Total				212
Optimized Algorithm
1	3	3	1	9
2	4	6	2	48
3	4	6	2	48
4	3	3	2	18
5	3	3	2	18
6	3	3	2	18
7	3	3	1	9
8	2	1	1	2
Total				170
Source: Developed by the authors.

Based on the obtained calculation results (Table 5), we will form conclusions about the effectiveness of optimization solutions (Table 6). The optimized algorithm unified procedures, reduced operational workload by 20%, and enhanced efficiency, scalability, and legal adaptability. Transitioning from fragmented interaction to a systemic regulatory model proved key for effective counterterrorism and investigation of terrorist crimes.

Table 6: Results of evaluating optimization efficiency of interagency cooperation algorithm in terrorist homicide investigations.
Indicator	Generalized Algorithm	Optimized Algorithm
Number of stages	8	8
Total operational complexity	212	170
Complexity reduction	–	≈20% reduction
Source: Developed by the authors.

Discussion

Our findings are compared with similar studies in the same research area below:

Furger emphasizes that JITs have limited practical effectiveness despite their regulatory attractiveness.²¹ Our study proves that national models with integrated management provide higher investigative performance. I Gusti Putu Bagus Pradana and Ihza Pamesti found that terrorist attacks in Indonesia mostly achieve tactical goals only.²² Our study emphasizes that interagency coordination is the determining factor in the effective investigation of such crimes. Jadoon et al. showed that the choice of US counterterrorism tools depends on administrative succession and changes in threats.²³ Instead, our study emphasizes the role of structural interagency cooperation as a key factor in an effective response. Barshep noted that the UN has become a key player in shaping the global response to terrorism over time.²⁴ Our study, however, emphasizes that institutionally enshrined interagency cooperation at the national level is crucial to effective investigation.

Bonsoms showed that the sustainability of counterterrorism engagement depends on institutional structure.²⁵ This study, however, emphasizes the importance of not only formal frameworks but also consistent communication and integration of functions between structures. Ojwang et al. noted that the lack of coordination and data sharing in Kenya reduces the effectiveness of counterterrorism.²⁶ This study emphasizes that addressing such problems requires structural integration, unified procedures and accountability. Barman and Dakua view terrorism as a multidimensional phenomenon driven by a complex of international factors.²⁷ At the same time, our study emphasizes domestic coordination of services as a key factor in the effective investigation of terrorist murders. Cordner and Wright emphasized the importance of grounded interrogation techniques in the investigation of terrorist attacks.²⁸ Our study focuses on institutional integration and unified procedures as determining factors for effective inter-agency cooperation.

Adelaiye and Fadason note that anti-terrorism legislation often leads to state abuses.²⁹ Instead, this study emphasizes that effectiveness is ensured by legal balance and transparent interdepartmental interaction. Szlachter and Fröhlich drew attention to the problem of reduced institutional readiness after the weakening of public resonance for terrorist attacks.³⁰ Our study emphasizes the need for constant structural interaction, which guarantees a stable response regardless of external influences. Comparison with related studies showed that legally regulated, structurally integrated interagency models are most effective in investigating terrorist homicides. Sustainable results arise from systematic, transparent, and coordinated service interaction within a unified algorithm.

Limitation

The main limitation is the inability to test the algorithm without political commitment from states and international bodies; its implementation requires both regulatory and managerial support. Additionally, the handling of sensitive and operational data was confined to open-source and declassified materials, ensuring compliance with legal and ethical standards. No access to confidential or classified information was undertaken, and therefore no formal ethics approval was required. Nevertheless, the study recognizes potential risks of over-centralization within interagency cooperation models including implications for civil liberties and due process. These risks were mitigated conceptually by embedding safeguards of legal proportionality, multi-level accountability, and judicial oversight mechanisms within the optimized algorithm’s design.

Recommendations

A pilot implementation of the optimized algorithm in a limited interagency format is recommended; positive results could justify scaling it nationally and internationally.

Conclusion

The study showed that effective investigation of terrorist homicides depends on formalized, legally regulated, and institutionally structured interagency cooperation. Analysis of 25 jurisdictions revealed four cooperation models, with hierarchical and analytically integrated types most effective. The resulting optimized algorithm reduced operational complexity by 20%, enhanced response speed, and transformed fragmented interaction into a unified counterterrorism system. The study’s novelty lies in formalizing typologies of procedural legal cooperation mechanisms and developing an optimized interagency algorithm based on structural cluster analysis of international experience. The practical value of the study lies in the applicability of the proposed algorithm within national and cross-border investigations, allowing adaptation to diverse legal systems and integration into existing counterterrorism mechanisms.

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Appendix

Table A1: Variable definitions and coding framework used in the analysis.
Variable	Definition	Coding Rule	Example
Subject (Au)	An institutional entity (agency, department, or unit) that performs an active procedural or analytical function in a specific stage of investigation.	Each legally mandated participant is counted once per stage. Subdivisions of the same agency are not double-counted.	FBI, DHS, and ATF = 3 subjects
Interaction (Vn)	A bilateral exchange of information, task coordination, or procedural cooperation between two subjects during a stage.	Each unique pairwise connection is counted as one interaction. Triangular or network exchanges are decomposed into dyadic pairs.	FBI ↔ DHS, DHS ↔ ATF, FBI ↔ ATF = 3 interactions
Procedural Complexity Coefficient (Cr)	Weighted indicator of legal and operational difficulty for a given stage. Reflects oversight, regulatory density, and cross-jurisdictional dependencies.	1 (low): standard procedure; 2 (medium): cross-functional coordination under standard law; 3 (high): multi-agency or judicially supervised activity.	Example: interagency evidence transfer with court warrant = 3

Table A2: Example of stage coding by jurisdiction.
Jurisdiction	Stage	Subjects (Ant	Interactions (Vn)	Complexity (Co)	So	Analytical Comment
USA (Patriot Act, FISA)	Intelligence integration (JTTF)	4 (FBI, DHS, ATF, CIA)	6	3	72	High procedural complexity due to multi-level data sharing and judicial oversight under FISA.
France (Code de la sécurité intérieure)	Coordination under DGSI	3 (DGSI, Gendarmerie, Police Nationale)	4	2	24	Centralized control ensures efficient vertical management but limited local adaptability.
Ukraine (SSU, National Police, PGO)	Evidence chain management	3 (SSU, NP, PGO)	5	3	45	Legal coherence present, yet procedural fragmentation across oblasts increases coordination cost.

Table A3: Legal frameworks and criteria for highly effective interagency cooperation models across selected jurisdictions and organizations.
№	Jurisdiction/ Organization	Primary Legal Sources	Time Frame Considered	Criteria for “Highly Effective” Model
1	United States	Patriot Act (2001); FISA (1978, amended 2008–2020)	2001–2023	Institutionalized JTTF structure integrating FBI, DHS, and ATF; continuous judicial oversight under FISA.
2	United Kingdom	Terrorism Act 2000; Investigatory Powers Act 2016	2000–2023	MI5–CT Police–CPS joint framework; codified data exchange; integrated judicial supervision.
3	France	Code de la sécurité intérieure	2012–2023	Centralized DGSI authority; vertical coordination; standardized intelligence workflows.
4	Germany	Grundgesetz; BKA-Gesetz	2006–2023	Federal–Länder synchronization via BKA; delegated investigation powers; inter-level accountability.
5	Italy	Codice Penale; D.Lgs. 159/2011	2011–2023	DDA–DIGOS integration; prosecutorial oversight; reduced procedural fragmentation.
6	Canada	Anti-Terrorism Act (2001); CSIS Act	2001–2023	Strategic CSIS–RCMP cooperation; privacy-security balance; stable multi-agency task forces.
7	Spain	Ley de Enjuiciamiento Criminal	2004–2023	Magistrate-guided police coordination; legal traceability of operations; transparent judicial workflow.
8	Australia	ASIO Act 1979; Criminal Code Act 1995 (CT provisions)	2001–2023	ASIO–AFP integration; federal-state alignment; national security coordination center.
9	Israel	Counter-Terrorism Law (2016)	2016–2023	Joint operational task forces among Shin Bet, Mossad, and Police; unified command structure.
10	Turkey	Law No. 3713 (Anti-Terror Law)	2005–2023	NSC-led coordination boards; permanent CT councils; structured inter-service hierarchy.
11	India	UAPA (1967, amended 2019); NIA Act (2008)	2008–2023	NIA-centered coordination; defined inter-jurisdictional mandates; state integration procedures.
12	Indonesia	UU Terorisme 5/2018	2018–2023	BNPT coordination across ministries; civil-military task units; integrated CT legislation.
13	Kenya	Prevention of Terrorism Act 2012	2012–2023	Multi-agency CT fusion center; defined inter-departmental protocols; unified data platform.
14	Nigeria	Terrorism Prevention Act (2011)	2011–2023	Joint intelligence-police-prosecutor cooperation; enhanced federal oversight.
15	Pakistan	Anti-Terrorism Act 1997	1997–2023	Provincial CTDs under federal command; procedural consistency in CT courts.
16	Ukraine	Criminal Code of Ukraine; Law on the Security Service of Ukraine	2014–2023	Integrated SSU–Police–PGO coordination; harmonized regional workflows.
17	Poland	Kodeks Karny; Ustawa o ABW	2002–2023	ABW-Police interagency operations; centralized counter-terrorist coordination bureau.
18	Sweden	Terrorism Act (2017:630)	2017–2023	SÄPO leadership in national CT policy; clear procedural division; provincial extensions.
19	Japan	Act on Punishment of Financing Terrorism (2002)	2002–2023	JAFIC–law enforcement cooperation; standardized financial intelligence system.
20	South Korea	Counter-Terrorism Act (2016)	2016–2023	MOIS-led intelligence center; nationwide inter-agency response plan.
21	European Union	Directive (EU) 2017/541; Europol Regulation (2016)	2017–2023	EUROPOL–Eurojust coordination; cross-border joint investigation teams; mutual recognition.
22	INTERPOL	Constitution of INTERPOL; Rules on the Processing of Data (RPF)	2000–2023	I-24/7 global intelligence exchange; standardized NCB operations.
23	United Nations	UN Charter; UNSC Resolution 1373 (2001); CTED Mandate	2001–2023	Global counter-terrorism coordination under CTED; inter-state peer monitoring.
24	NATO	North Atlantic Treaty; STANAG 2525	2002–2023	Combined Joint Task Forces (CTF); standardized interoperability protocols.
25	Shanghai Cooperation Organization (SCO)	SCO Charter; RATS Agreement (2004)	2004–2023	RATS database exchange; institutionalized multi-national intelligence cooperation.

Cite this article as:
Demidov I, Hadzhiieva A, Tkachov I, Kozenko O and Bohdan D. Efficiency of Cooperation Between Various Services and Specialists in the Investigation of Terrorist Murders: Development of an Optimized Algorithm. Premier Journal of Science 2026;16:100240

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