There are a number of reasons you could be asked to an informal meeting without receiving a formal allegation of misconduct.
One purpose of an informal meeting can be to help educate students about academic integrity rules. For example, subject coordinators have the authority to identify an incident of "poor academic practice", where they can implement an ‘educative’ response, which could result in you being advised on correct referencing techniques, or to complete some learning materials on academic integrity. You may also be asked to revise and resubmit work after fixing minor issues with referencing or citations. These are all supposed to be helpful, educative, tools to help you avoid serious issues in the future.
You may also be asked to attend a meeting where you’re not told very much about what you're going to be discussing, which can be a bit scary. These kinds of meetings may be called because staff may see a possibility that there has been a misunderstanding that you could potentially clarify, or they may suspect you have done something not quite right and they want to know more. Meetings like this should be focussed on staff trying to understand more fully what has happened so they can decide what they might need to do in response. These conversations need to be fair and polite and ultimately are designed to try and help you understand academic integrity rules clearly.
As explained above, the University bears the burden of proof in making a case against you if they think you have breached the rules. There are several ways they can collect enough evidence to support a formal allegation. For instance, they can ask you questions about how you completed your assignment or ask you to show how you came about a particular answer. However, they are not permitted to search for incriminating information from you or ask you leading questions about academic misconduct to help them build their case against you. This includes asking you to confess information for fear of things becoming much worse if you don’t comply.
During the course of an informal meeting, if it appears that deliberate and significant Academic Misconduct has occurred, the teaching staff must end the meeting and inform you that they intend to pursue a formal allegation. Informal meetings cannot be used as substitutes for proper, formal hearings. No penalties for misconduct can be applied as a result of an informal meeting. Only after a matter is formally heard by a formal committee/faculty academic integrity officer, and a student has been given the chance to respond in writing and attend the hearing, can it be decided whether you have committed Academic Misconduct or not. If they form this view, only then can any penalties be applied.
It is important that you know that anything discussed at a meeting of this kind could be used to formalise an allegation of misconduct against you. We suggest you ask some more questions to help you prepare. It can certainly be alarming to receive an email asking you to attend a meeting when you don’t know what it is about. Rest assured, you are absolutely within your rights to request more information before you turn up.