The friar's tale (canterbuty tale)

This story concerns a Summoner who is paid by a Bishop to summon sinners for Trial before the Church Court.

This particular Summoner has a team of spies and harlots who provide him with information concerning those living in the Parish, and the Summoner gathers this information to be used against them by the Church.  The Summoner blackmails the Parishioners to prevent him revealing the information to the Church Court.

The summoners' tale ( canterbury tales)
The Summoner's Tale is one of The Canterbury Tales by Geoffrey Chaucer.
The tale is a fierce counterpunch to the preceding tale by The Friar which had been an offensive attack on summoners. Summoners were officials in ecclesiastical courts who summoned people to attend and worked in a similar way to ushers. The Friar had accused them of corruption and taking bribes and the Summoner seeks redress through his own story.