Possible Clues:

• Tony Short added fungi raised on the farm as part of the bill
• The section of the Metropolitan Police that was once concerned with national security?
• Bishop arrested by new Lancashire PC in force
• Select arm for security team
• Police department: important local office
• Police department dealing with political security
• Police department
• Police clear chap's bin in error
• Police held in particular esteem at local office
• Police responsible for political security