Possible Clues:

• Marks man, say, as second rep in trouble
• Sneaky critic
• One taking potshots
• Critic cut the Queen
• Person who works on the roof?
• Marksman holds up fire -- pin stuck a bit
• He criticises one who takes pot from a safe place
• One who works on the roof?
• Rifleman firing from concealed location
• Marksman in hiding place