The Universal Translator is the most ubiquitous technology in all of Star Trek, but it's also the least explained. It's just magic, and always works exactly according to the needs of the plot.
The interesting thing about the trial scene is that there's no UT - it's a person manually translating. Which suggests the UT confiscation happened before the trial.
There's also the question of whether the use of a particular language is diegetic or not, and the film clearly switches between them as needed. The trial again shows this in real time - Chang starts in Klingon, then we cut to the translator, and back to Chang now speaking English for the audience's benefit. But he's still diegetically speaking Klingon.
I think the only time that Kirk speaks Klingon on screen is when he imitates Kruge calling for a beam up on Genesis. And that's not conclusive, as it's simple mimicry.
The interesting thing about the trial scene is that there's no UT - it's a person manually translating. Which suggests the UT confiscation happened before the trial.
There's also the question of whether the use of a particular language is diegetic or not, and the film clearly switches between them as needed. The trial again shows this in real time - Chang starts in Klingon, then we cut to the translator, and back to Chang now speaking English for the audience's benefit. But he's still diegetically speaking Klingon.
Could be, but Chang is primarily playing to the gallery. Either way, Kirk pauses before responding, allowing enough time for the translation.I know Chang was quoting Adlai Stevenson at the trial, but the implication when he tells Kirk to not "wait for the translation" is that Kirk speaks Klingon and Chang knows it.
I think the only time that Kirk speaks Klingon on screen is when he imitates Kruge calling for a beam up on Genesis. And that's not conclusive, as it's simple mimicry.

