purple judge

So called because in most cases their dress code would include a purple or lilac robe or sash or tippet of some kind.

purple judge (plural purple judges)

1. (UK, law) A circuit court judge.
   • 2012, David Kelly, Gary Slapper, Sourcebook on English Legal System, page 174:

     The criminal defendant sees a difference between a 'red judge' and a purple judge.

• red judge