The king wants a new tax. Delamere asks for charge of all the poor of the land, to hang them; better they hang than starve. A lord says he deserves death, but Devonshire, fighting for Delamere, kills the lord and finds he is wearing the king's armor
This sort of gesture of defiance (compare Swift's "A Modest Proposal") is much more common in story than truth; there is no reason to believe that the events here ever took place. Child gives what background there can be.
The one interesting point I observe is that the lords involved were mostly active at the time of the Glorious Revolution (1688) -- and, what's more, Lord Delamore (1652-1694) and William Cavendish, Earl of Devonshire (1641-1707; Duke of Devonshire from 1694) both gave open support to William of Orange. Delamere, in fact, went on to be one of the Lords of the Treasury.
Perhaps this originated as some sort of Williamite broadside? Or, perhaps, an attempt to save Devonshire from protests? (He is said to have been poor about paying tradesmen.) - RBW