For this shoot, the films production designer, Herman Zimmerman, found that "Even though I still had the next largest stage on the lot at my disposal, it wasn't quite big enough to do the courtroom I'd originally intended, so we had to scale it down somewhat." Ironically, that ended up working to the film's advantage, for the production was limited to 65 Klingon extras, but had to make it look like there were 3,000. Zimmerman explained, "The smaller set actually helped me convey the sense of a much larger audience; though we only had three rows of Klingons, we implied that there were many tiers above that, each containing another 50 Klingons. We were also helped by a matte painting, a downshot of the entire courtroom that augmented our real set and which will convince the audience that all of those Klingons were really there." (Charting the Undiscovered Country: The Making of Trek VI, p. 86)
"The Klingons seen in the most distant reaches of the gallery, as glimpsed in the first establishing shot of the scene, were a miniature set filled with two hundred Worf dolls. These 1/72 scale Worfs moved back and forth through the used of cams attached to motors run by the motion control system. Small Christmas lights suggested the lighted spears. They filmed the miniature set on its side in a smoke-filled room to get a murky Klingon atmosphere. They crew added live action elements of Kirk and McCoy imprisoned in a pillar of light and actors in Klingon attire in the uppermost tiers with the matte painting of Klingons in the gallery." (Trek: The Unauthorized Story of the Movies, p. 173)
In 2293, these three judges presided over the trial of Captain James Kirk and Doctor Leonard McCoy after they were accused of involvement in the assassination of Chancellor Gorkon.
The trio of judges consisted of an albino Klingon speaker and two other judges who, like the albino, wore hoods embroidered with Klingon lettering but, unlike most Klingons (including the speaker), were not bearded. Kirk and McCoy were found guilty, but the albino judge commuted the sentence to life imprisonment on Rura Penthe, in light of the circumstantial nature of the evidence and to foster amity in the peace talks. (Star Trek VI: The Undiscovered Country)
The judge, listed in the end credits of Star Trek VI simply as "Klingon Judge", was played by actor Robert Easton. His makeup and facial hair was applied by Margaret Prentice. 
In filming the scene, cinematographer Hiro Narita described that the lighting of the scene was done just so because "the judge was an albino, so he had a very pale face and white hair that was almost hidden under a large black hooded cape. Nick wanted this white face only to become visible occasionally, so I aimed a little spotlight at him from above so you only see the judge's nose and forehead when he leans forward into the light. That was the kind of thing I really enjoyed on this film." (Charting the Undiscovered Country: The Making of Trek VI, p. 70)
Warning! This section may contain spoilers for new Star Trek material.
L'Rell's mother was a member of the House of Mo'Kai. When her daughter came of age, she presented L'Rell with a knife and demanded she cut her own heart in half if she would not choose to belong to either the House of Mo'Kai or the House of T'Kuvma, due to the heavy feuds between the Klingon Houses during this time period. Instead, L'Rell chose to build a bridge between the houses. (DIS: "The Butcher's Knife Cares Not for the Lamb's Cry")