Green’s Dictionary of Slang

frequent flyer n.

a lit. or fig. recidivist.

[UK]Secret Barrister 282: Frequent flyers become well acquainted with the judicial personalities in their local courts.
[UK]‘Secret Barrister’ Fake Law 273: Constituency MPs making hay over ‘soft judges’ passing insufficiently punitive sentences [...] is a common theme. One frequent flyer is Philip Davies MP.