Possible Clues:

• Brash young man
• Brash, cocky young man
• Flashy, cocksure young man
• Young rogue tackled a judge vigorously about heroin
• Cocky youth after lift halted convertible
• Young fellow seen as a 'card'?
• Flash bloke, knave held at resort
• Cocky boy
• John-Boy, the exhibitionist
• Young show-off