HMRC have published new qualitative research on the attitudes of those given custodial sentences for tax evasion.
I have not read it all in detail - but have scanned it and see some issues of real concern with the document, including this statement:
Whilst not cited as a reason for committing tax evasion, it was clear that negative views of tax and perceptions of an unfair tax system sometimes underpinned offending.
I think writing in answers from witnesses an unusual thing to do in such work.
That said, for those interested in this area this is new research, and worth a look so I give it a nod.