We've spotted Arun on his way to the courthouse multiple times since jury selection in Diddy's trial began ... and, he's always looked down to earth -- headphones on, no indication he's a federal judge.
Diddy Judge Arun Subramanian Looks Like He's Heading to School
Diddy judge Arun Subramanian looked more like a student heading into a building to attend class today -- instead of his day job,..
TMZ