Just a futuristic version of what a High Court judge would look like.
If he'd been given a horsehair wig, that would've been a little too much like a specific attack on the British legal system.
I know some like all the specific detail about WWIII, like who the flags belong to in that courtroom - a facist looking black eagle on a red banner. The Optimum according to the novel Federation incidentally - a military dictatorship that spread across western nations. Whereas the other main power block, the ECON got mentioned onscreen in First Contact.
I'm uncertain about all that myself. In a way, some like to think of Star Trek's universe as our future. Too much information about its past, quickly becomes outdated for us.
Then again, Star Trek's universe is more parallel with some of it already in our past, like Khan being from the 1990's or any realistic chance of making first contact with Vulcans in the next 50 years frankly.
So when they produce TV shows and films, they go with what they think millions of people watching can swallow. More often than not, keeping the tiny details vague and open to reinterpretation. Obviously throwing dates and names in there and it gets specific. 1996 Eugenics War ends. 2063. First Contact in Montana, with presumably WWIII still going on elsewhere in the world. Given the courtroom in Encounter at Farpoint is 2079.
It's an interesting thing... Star Trek's message. With it's utopian view of the far future, but a really nasty dystopian one pretty much within the lifetime of the audience watching. For their kids and grandkids. Both TOS and TNG pretty much espoused us getting to the stars, but through lots and lots of hardship. Somewhat easier for a 24th Century crew to sell that "hang in there baby" attitude to Zefram Cochrane, than say anybody else coming back closer to our present day.