Possible Clues:

• One who demonstrates in favour of examiner
• Someone being vocal about "beef" from nag that's fed baloney
• Person, we hear, not content to perish during plague
• Hector about the corruption and he objects
• One may be striking
• Demonstrator
• ''Nonsense!'' interposed to hector the demonstrator
• Member of the mob?
• Riot squad's opponent
• Hound made to eat tripe? I strongly object