The actual location of Gyakuten Saiban / Ace Attorney?

Solution 1:

I couldn't find any clear evidence whether the Ace Attorney games take place in Los Angeles specifically, but an interview with the official English translator reveals the following:

Take a look at the characters, environments, and cultural references of Ace Attorney, and it's hard to ignore the game takes place in Japan. Contrary to this surrounding evidence, the English language version of the game establishes the setting as the United States, all thanks to a single piece of evidence from the very first chapter. Though this choice would become less believable with each passing sequel, Smith explains how his hands were tied on the matter: "Normally, what you do in a situation like that is leave [the location] vague. You just say, 'Hey, we're in Nowhere Land,' and you adapt the cultural references that will go over the heads of your audience. The specificity of the setting had to be made because there was an episode where this guy has some sort of clock his girlfriend gave him. It had to be set to some time zone, and we were like, 'Oh, crap. I guess we have to be specific about it.' So we just chose that without really thinking that much about it. And I know this has become an issue in later games, especially—the difficulty in selling where the game is set. The Japanese references have gotten layered on heavier and heavier and heavier."

Emphasis mine.

So as you can see, the game is originally located in Japan, but was moved to the US in the English version.