Input data and information sources
The system analyses images and voices of people who control their own behaviour and can disguise it. The system processes identifiable people's faces or voices.
The system infers a person's emotions or intentions from their face, voice or behaviour.
Understand the use case
Trials have taken place at UK railway stations and in an EU research project at border crossings.
This page describes a typical system design. Actual data flows and permissions depend on your implementation.
System design and data flows
The system receives camera images, voice recordings or other bodily signals from a person.
The system analyses images and voices of people who control their own behaviour and can disguise it. Some systems analyse face and voice together; others use only one.
The model recognises expressions, tone or movement and infers an emotion such as joy, anger or fear, or an intention such as deception.
The model processes characteristics of the face, voice or other signals and assigns an emotion category or assessment. It thus infers a state that cannot be observed directly from external signals. The resulting category is a model interpretation rather than a direct measurement of subjective experience.
The system assigns an emotion and numerical score to each person or group.
The result describes the defined model task. A match, category or forecast acquires its professional significance only in conjunction with the underlying data and intended use.
The output feeds into analysis or influences how workers, customers or travellers are treated.
Integration determines whether the result is simply displayed, adopted after approval or written directly into a business application. These variants differ in their data flows and permissions.
Explore the system design: Select a component to see its task, incoming and outgoing data, and role in the use case. The guided walkthrough explains each phase. Then use Yes, Uncertain and No to represent your specific system variant.
7 review first10 clarify7 baseline threats
The diagram shows the typical architecture. Select a component to see what happens there and adapt its features to your system. Enable “Analysis guidance” to see which threats need reviewing for this architecture. The page's checklist continues to describe the typical case.
None yet. Each change will appear here.
In this system design: 7 to review first, 10 to clarify, 7 baseline threats.
External access: Depends on your system
To clarify
Input: Part of every AI system
Review first
To clarify
Third-party content: Present
AI model: Part of every AI system
Baseline for every AI system
Provider service: Present
Review first
To clarify
Training and feedback: Present
Review first
To clarify
Result: Part of every AI system
Baseline for every AI system
Business application or equipment: Depends on your system
To clarify
person: Part of every AI system
Review first
Affected person: Depends on your system
Unapproved AI services: Depends on your system
To clarify
Supply chain and technical foundations: 5 baseline threats applying to every AI system
Baseline for every AI system
Text analytics for feedback and consultation responses
Determines sentiment in written text
Remote biometric identification (facial recognition)
Identifies a person from their face rather than determining their emotions
The system analyses images and voices of people who control their own behaviour and can disguise it. The system processes identifiable people's faces or voices.
Deployers use ready-made services, such as Amazon Rekognition at Network Rail.
Logging, retention periods and possible use for training must be established for the specific implementation.
If a cloud service analyses the images, they leave the organisation's environment.
Using a provider does not automatically determine where processing takes place. Storage location, subcontractors, deletion periods and use for training must be checked for the specific deployment.
Assess risks and determine measures
Record data, participants, interfaces and permissions. Resolve uncertain characteristics in the model.
Relate review candidates to actual data flows: what could happen, and who would be affected?
Assess impacts and likelihood in the deployment context. The number of review candidates is not a risk score.
Select appropriate controls, assign responsibilities and define effectiveness checks. Document residual risks and approvals.
A total of 24 threats from the threat catalogue may be relevant to this use case.
Facial expressions do not reliably reveal feelings and differ across cultures and individuals. Trusting the output may label a tense traveller suspicious or a calm worker unmotivated.
People can deliberately control their expressions and tone when they know they are observed. The system then attributes calmness or honesty where neither exists.
Sensitive Information Disclosure
The system records its attributed emotion for each recording. If these labels leak with an image or name, individuals' supposed moods, fears or intentions become known.
Targeted Poisoning / Label Poisoning
Falsified training labels can deliberately shift model outputs.
Listed because of this characteristic
Training data or an adopted base model can introduce hidden triggers for misbehaviour.
Listed because of this characteristic
Targeted queries can recover some personal or protected training data from the model.
Listed because of these characteristics
Exfiltration from ML Application
Protected data can leak through tools, network connections, storage or insiders.
Listed because of this characteristic
Up to 10 further threats may apply, depending on your system design. Nine threats need to be reviewed for every AI system. Two of these are particularly important here and are therefore listed above.
Each Yes adds further threats to your checklist, up to 10 in total. If you cannot yet answer a question, include its threats in your review.
How your system is built
How you operate the system
If yes, add
If yes, add
If yes, add
Some systems analyse face and voice together; others use only one.
If yes, add
These questions arise for almost every AI system.
If yes, add
With a cloud service, camera images travel over the network for analysis.
If yes, add
If yes, add
If yes, add
If yes, add
If yes, add
Measures for the priority review areas are expanded. Each linked measure explains how to implement it.
Controls for the remaining threats are available on their pages in the threat catalogue.
For every AI system Applies since 2 February 2025.
In typical use Review trigger since 2 February 2025.
Depending on use Review trigger since 2 August 2026.
In typical use Review trigger from 2 December 2027.
Depending on use Review trigger from 2 December 2027.
Applies if staff or appointed representatives operate or use AI systems.
Applies since 2 February 2025.
Detailed obligations
Applies if the system recognises workers' emotions in the workplace or learners' emotions in an educational institution, except where used for medical or safety reasons.
Applies since 2 February 2025.
Detailed obligations
Applies if the system infers emotions or intentions from the faces, voices or bodily signals of people other than workers or learners, such as travellers or telephone customers.
Applies from 2 December 2027.
Detailed obligations
Applies if authorities use the system at borders or in asylum procedures to detect deception, as trialled by the iBorderCtrl research project.
Applies from 2 December 2027.
Detailed obligations
Applies if people are exposed to the system, for example at a station or during a customer conversation.
Applies since 2 August 2026.
Detailed obligations
Classify your system with the quick checker All obligations in the obligations compass
Review these threats for every AI system, whatever its purpose.
If any of these features does apply to your system, add the listed threats.
Does the system generate its own text, such as answers, drafts or summaries?
The system produces an emotion label or score for each person, rather than text.
If yes, add
Does the system generate or edit images, sounds, voices or videos?
If yes, add
Does the system create new content from open-ended requests that people read, see or hear directly? Translation, reading aloud and transcription do not count.
If yes, add
Can users give the system natural language tasks that it then performs?
If yes, add
Does the system search its own collection of documents or records for relevant content?
If yes, add
Does the system formulate answers from retrieved documents?
If yes, add
Does the system use a knowledge graph storing concepts and their relationships?
If yes, add
Does the system remember content from earlier conversations or tasks and reuse it later?
If yes, add
Does the system call other programs, interfaces or search services itself, even if only to read?
If yes, add
Does the system determine its next steps itself based on earlier results?
If yes, add
Does the system delegate tasks to other AI agents or incorporate their results?
If yes, add
Is the system connected to tools or data sources through the Model Context Protocol (MCP)?
If yes, add
Do documents from several customers, departments or permission groups share one search store?
If yes, add
Does the system generate code, scripts or database queries for further use?
If yes, add
Does the system execute programs, scripts or commands itself?
If yes, add
Is the system intended to maximise a specified metric, such as revenue, utilisation or clicks?
If yes, add
European Commission, Guidelines on prohibited AI practices, 2025
The Commission explains that recognising call centre workers' emotions is prohibited, whereas analysing customers' emotions is not.
EU AI Act, Annex III, point 1(c)
The Act expressly lists emotion recognition systems in Annex III where they are not prohibited.
Federal Network Agency, Prohibited practices
The agency gives the example of a webcam used to detect workers' anger.
DIGIT, Hidden AI Cameras Recorded Train Passengers’ Emotions at Glasgow Central, 19 June 2024
The report describes an emotion analysis trial at several UK railway stations.
CORDIS, iBorderCtrl (Grant 700626), Reporting page
The page describes deception detection as part of a border control system and trials in three countries.
Updated: 30 September 2026. Review checklist rules version 0.3.2, threat catalogue version 2026.10.24.2. How these pages are structured