You 'are allowed' to ask any questions you want. You can ask permission to bring any witnesses you want. But most of what you want to do in this post is completely pointless. Please read my post again. You need to concentrate on answering the allegations. Questions about how the allegation information was gathered are meaningless in that context. Answer the allegations - that is all you need to do. The more you go on about what questions were asked, or whether they were asked or who else was involved just makes you sound defensive and desperately looking to get the allegations ignored. It does not help your case. Believe me I have represented employees in disciplinary hearings more times than I can remember over a 16 year period. Just answer the allegations. And they don't have to prove beyond doubt that you have broken the rules - that is the standard of proof for criminal cases. Your employer merely has to believe on the balance of probabilities and on the basis of credible evidence, that you have broken the rules.