Possible Clues:

• Port with volunteers in front of court as a means of controlling disorder?
• Reprimander's "reading"
• Cereal infected, you might say, resulting in severe reprimand
• I love diplomacy after end to war -- it can restore order
• This is read for a severe warning
• Warning traitor regularly on diplomacy
• *Severe reprimand, in metaphor
• Brazilian city needs diplomacy for control of civil disorder
• Diplomatic activity following port order to quell trouble
• Old means of crowd control