On this page:

1. What is fraud
2. Prevention
   1. Prevention by teaching about academic integrity
   2. Authorised use of GenAI
   3. Anti-fraud measures

3. Detection
   1. Detection by Turnitin
   2. Detection through your own observations

What is fraud

Fraud is defined as: 

Any act or omission of a student that makes it completely or partly impossible for the examiner to form a correct assessment of the student’s knowledge, understanding, skills, (professional) attitude or reflection. 

Plagiarism is a type of fraud. 

Prevention

Prevention by teaching about academic integrity 

The best way to reduce the risk of fraud and plagiarism is to engage in a recurring conversation with students, from the start of their study programme, about learning, assessment and academic integrity. Students need to realise that a university degree represents specific academic and scientific knowledge and skills, for the academic world and for society as a whole. Fraud and plagiarism are therefore regarded as serious offences, for which severe penalties may be imposed. For this reason, you should emphasise that students must be able to demonstrate independently that they have achieved the learning objectives, and that it is their own responsibility to show with integrity what knowledge and skills they have gained.

Ideally, agreements have been made within a study programme about which aspects of (academic) integrity are explicitly covered and where they are situated in the curriculum. Ask the programme director or education coordinator whether such agreements exist. If not, you should discuss this with your colleagues, ensuring that the students receive clear and consistent information. 

Authorised use of GenAI

As an examiner, you can decide for yourself whether and how students are permitted to use GenAI when completing assignments. You should communicate this to the students very explicitly (e.g. in Brightspace), also stating how they should cite GenAI as a source or tool, if applicable.

There may be good reasons to permit students to use GenAI in their assignments; for example, to search for information, in a brainstorming process, as a tool when editing their own text, or even as an assessment format, where students are asked to analyse GenAI-produced text in terms of content or structure.

Agreements may already have been made within the study programme about how students are permitted to use GenAI in which phases of the study programme. You should ask the programme director or education coordinator about this.

For more general information on the challenges and opportunities offered by these developments, see: AI as challenge and support [link]. 

Anti-fraud measures

In addition to an ongoing focus on integrity in your teaching, there are also more practical measures you can take to reduce the risk of fraud (cheating). The importance of a specific assessment is also a factor in these measures: the consequences of fraud are much less significant for a formative assessment, or one that makes a very minor contribution to the final grade, than for exams that determine the final grade and the award of credits. 

A few tips and points to consider: 

General and organisational measures 

• Don’t let the final grade depend on just a single assessment; use multiple assessment moments (constituent assessments). 
• Design assessments with questions at higher cognitive levels, such as questions or case studies aimed at analysis and evaluation. Questions relating to knowledge and understanding (lower cognitive levels) are usually more susceptible to fraud. 
• When constructing assessments, but also when storing them later, make sure that (digital) documents are stored securely, or that drafts for review are shared securely with colleagues. It is highly damaging if questions are leaked in advance. 
• The inspection session after an assessment can be susceptible to fraud: an answer can be changed or exam questions can be copied without authorisation. 

Measures against misuse of generative AI 

Some tips specifically aimed at reducing the risk of fraud through unauthorised use of GenAI: 

• Inform students very clearly about whether and how they are permitted to use GenAI when completing assignments. Explain why, and also state explicitly what the consequences of unauthorised use of GenAI will be. 
• Check in advance what (the most well-known) GenAI software is capable of producing in relation to your assessment. 
• Think about whether workload and time pressure could be significant reasons for students to consider using GenAI. Might a different balance between formative and summative assessments, or more time between deadlines, perhaps reduce this inclination? 
• Give students written assignments to produce on campus, with an invigilator, instead of at home. 
• Combine written assignments with other assessment formats that are less susceptible to unauthorised use of GenAI, such as oral presentations, or other types of written assessment (on campus). 

Anti-fraud measures when administering assessments 

• For tips to prevent fraud (cheating) when administering assessments and information on invigilation, see also: Administering assessments – Fraud prevention.

Detection  

While the most important aim is to prevent fraud and plagiarism, another essential element of safeguarding academic integrity is detecting and punishing them. Although it can be difficult for you to establish precisely whether fraud or plagiarism has been committed, or unauthorised use of GenAI has taken place, there are a number of tools and indications. 

Detection by Turnitin

Turnitin is an external tool that has been integrated in Brightspace to grade assignments, papers and suchlike, and to check them for plagiarism. It helps you with detecting plagiarism by comparing submitted essays with a large database of academic sources, websites and previously submitted essays and theses. It flags similarities and gives a detailed report, showing which parts of an essay may have been plagiarised without correct source citation. 

Please note: Turnitin is not enabled as standard in Brightspace, so always remember to tick the Turnitin box if you want completed assignments to be checked for plagiarism.

Turnitin is not suitable for detecting GenAI-produced texts, but it can be helpful in checking for sources that were fabricated by GenAI. Usually, sources are highlighted in yellow by Turnitin, because there is similarity to existing text, but when GenAI has invented sources, Turnitin will regard the text as original and therefore will not highlight it. 

There’s a growing number of tools aimed at detecting GenAI. Unfortunately at present, and probably also in the near future, these tools do not meet a standard that justifies confronting the student with the result. 

For more information, see All about Turnitin or send an email to ECOLe. 

Detection through your own observations

In addition to using Turnitin, there are other ways you can check essays for plagiarism using your own observations. 

Similarities between students

If parts of essays written by different students show strong similarities in terms of content (and writing style), there may have been unauthorised use of GenAI or other forms of fraud.

Writing style

If the writing style is different from the student’s usual style, or if there are style changes within an essay, this may be evidence of fraud or plagiarism. You could perhaps ask the opinion of a colleague who is familiar with the student’s language use and vocabulary. 

The use of GenAI can sometimes be identified from the following elements: 

• Repetitive or long-winded formulations 
• Excessive use of specific words or expressions 
• Excessive use of adjectives and relative clauses 
• Incorrect or inconsistent use of first- and third-person perspective 
• Illogical construction of arguments 
• Limited variation in sentence structure 
• (Abundant) use of exaggerated, formal or unnatural language (or too little informal language) 
• Lack of personal flair or individuality 

However, GenAI software and LLMs are developing rapidly and their output is constantly improving, with ‘natural’ texts, a larger vocabulary and a high level of creativity. 

Unexpected knowledge or ideas 

If the essay contains knowledge, insights or (abstract) ideas that you suspect the student doesn’t actually understand, this may be evidence of using GenAI.

Untruths and suchlike

GenAI can generate untruths, maths errors and illogical or inconsistent answers with strong conviction.

Source citation

GenAI can cite sources that don’t exist or whose content doesn’t correspond to the references in the essay. The absence of sources can naturally also indicate fraud or plagiarism. You should therefore always check sources and references very carefully.

Meer informatie

• Gedragscode plagiaat Universiteit Leiden 
• Regels en Richtlijnen van de examencommissies 
• GenAI en LLM's in de academische gemeenschap, online module voor als je meer wilt weten over grote taalmodellen (LLMs)  en GenAI. 
• AI in het onderwijs 
• ChatGPT: Wat kan (en mag) er?