I'm having a hard time with this sentence:
Professional bodies will monitor, and if necessary, discipline members who do not adhere to their ethical principles.
Does 'their' refer to the members or to the professional bodies?
I agree with @Nigel J in that the sentence is ambiguous, but if I had to guess:
'Their' refers to the professional bodies.
From a practical standpoint, a professional body probably doesn't exist to enforce one member's set of ethical principles, which may differ from one member to another. Rather, a professional body likely exists to enforce the agreed-upon ethical principles of an organization with which that professional body is associated.