Please note: The algorithm descriptions in English have been automatically translated. Errors may have been introduced in this process. For the original descriptions, go to the Dutch version of the Algorithm Register.
Crime Anticipation System (CAS)
- Publication category
- Other algorithms
- Impact assessment
- IAMA
- Status
- Out of use
General information
Theme
Begin date
End date
Contact information
Responsible use
Goal and impact
The police regularly evaluates its algorithms. Following one such evaluation session, it was decided to phase out CAS from 1 December 2025.
CAS provides information to police teams about where and when crime is likely to occur. Police can be extra active in those boxes (see "technical operation") and at those times.
Considerations
The advantage of CAS is that people and resources can be used more effectively to enhance security. A disadvantage is that CAS is based on reports and notifications from citizens. If no crime reports or notifications have been made, it does not always mean that no additional police deployment is needed.
The deployment of CAS is justified because CAS provides important information for the police. But the results of CAS are not the only way to determine what police deployment is needed. Information about crime also comes to the police through other means, such as the neighbourhood police officer.
Human intervention
Staff at the so-called information hub of a police team process CAS outcomes, also using other police information. They process this data into a recommendation for the deployment of people and resources.
Risk management
A Human Rights and Algorithms Impact Assessment (IAMA) was carried out for CAS to determine what risks exist and how we can minimise them. Every year, these risks are critically examined and also possible new risks.
Legal basis
The legal basis of CAS deployment is described in Article 3 of the Police Act. The deployment of CAS falls under the daily police task. CAS helps to prioritise and choose where capacity is deployed. The legal basis for processing police data is laid down in Articles 8 and 13 of the Wpg (Police Data Act).
Links to legal bases
- Police Act article 3: https://wetten.overheid.nl/BWBR0031788/2023-02-18/#Hoofdstuk2_Paragraaf2.1_Artikel3
- Wpg article 8: https://wetten.overheid.nl/BWBR0022463/2022-10-01/#Paragraaf2_Artikel8
- Wpg article 13: https://wetten.overheid.nl/BWBR0022463/2022-10-01/#Paragraaf2_Artikel13
Impact assessment
Operations
Data
Technical design
The area of a specific police team is divided into 125m by 125m squares. Of these compartments, using historical police records, the following is calculated:
- how many incidents of a particular type of crime occurred in or around the compartment in a 12-week period;
- how many known suspects of that type of crime lived in the vicinity of the compartment during this period.
With these indicators, CAS can build an expectation for the boxes. This is done by a combined logistic regression model. That model is able to estimate the probability of an incident of a particular type of crime occurring in the near future based on the indicators mentioned above.
Using the indicators mentioned above and the logistic regression model, a police team can see in which boxes and at what times there is an increased risk of a certain type of crime. These boxes are then displayed on a map. A police team can request images of up to four types of crime to depict on a CAS map.