I am not sure I am following the logic in your argument. However, it is quite simple. If an individual is not the sole writer of a dissertation, they don't get a doctorate. If they pretend to, but purchasing someone else's work, they have committed fraud. It another person is a party to that act, then they are an accessory to the crime. Not sure where you are going with this, but it's really quite straight forward in Canada. All professors and grad students at the universities that I have attended are required to know this and sign that they have read the policy statement regarding such acts.
Thanks for your response. I didn't mean to provoke you.
My line of thought, for what it is worth, is that the writing of theses, essays, notes, proposals, etc., is not in itself illegal. It is the being party to fraud, the misrepresentation of authorship, that is illegal. So Coles Notes are not illegal, but it is wrong for a student to copy from them and present it as their work.
Now the guys who offer to write your thesis for you in return for payment will, I suspect, pretend (if they are caught) that what they are doing is really just writing a superior form of Coles Notes. The actual misrepresentation will be done by the student - the authors of the paid for thesis will say they didn't hand it in as the student's work, they just offered him a superior form of assistance and he decided to misrepresent that assistance as his own work. So they will get off scot free.
Ah well, You and I really agree - I am not disputing your insight at all.