Possible Clues:

• Fences of upright metal bars
• Iron bars set into protective fence
• Pale with ravings
• Loops put round excellent line in barriers
• Calls about trouble with barriers
• Such abuse has them paling
• Immoderate talk to keep one out
• They may prevent you from getting bumped off a flight
• Making a protest, start to slash barriers
• Trouble infiltrating gangs in bars