Sentence:  The law was served by a <WSD>skulk</WSD> of informers, who traded their whispers to the royal foresters and woodwards, who gilded their tales for the verderers and regarders, who presented the guilty to the forest Justices. 
Meaning of the word marked with <WSD> tags:  A group of people seen as being fox-like ("e.g." cunning, dishonest, or having nefarious plans).