There's a rather enjoyable series on Channel 4 at the moment: City of Vice, set in the early days of London's first official police force, the Bow Street Runners. While it's obviously fictionalised, it is accurate in spirit in highlighting the talents of the Fielding brothers.
The work as a magistrate of Henry Fielding is less known than his career as dramatist, satirist and author (notably of Tom Jones). The career of his half-brother, John Fielding, was equally remarkable; despite being blinded in a naval accident at 19, he went in business and studied law, eventually taking up his brother's post as Chief Magistrate on the latter's death in 1754, and continuing for 26 years as the "Blind Beak of Bow Street" (see also Sir John Fielding and Public Justice: The Bow Street Magistrates' Court, 1754–1780). He's the subject of a series of crime novels, starting with Blind Justice, by Bruce Alexander.
Not to forget a third talented member of the Fielding family: the critic and novelist Sarah Fielding, whose works included The Adventures of David Simple and The Governess, of The Little Female Academy, the first full-length novel written for children.
Addendum: City of Vice portrays John Fielding as constantly wearing a black headband, and this is a slight puzzle. This is how he's depicted in portraits (see the National Portrait Gallery Nathaniel Hone portrait and this engraving). But I rather wonder if he normally wore it covering his eyes, and pushed it up to give the portraits a more personal touch. A contemporary description by Samuel Curwen described him as "having a black fillet over his eyes". But does "over" mean "above" or "covering"? Go figure. - Ray