Whatās the best system for running an Ace Attorney style legal battle (complete with over-the-top shenanigans)?
Iām tempted to say Sea Dracula, but that would be a lie - Sea Dracula fosters a very different sort of shenanigans from Ace Attorney.
(Though if youāre curious what a game of courtroom drama that uses dance-offs as its conflict resolution system - yes, as in the players physically get up and dance, while any uninvolved parties act as judges - you should check it out. Itās only a dollar.)
Honestly, if youāre looking for something rules light Iād probably just run it in Fate Accelerated Edition. FAE is good for most premises where all of the player characters have basically identical descriptive capabilities and success and failure typically boil down to how their personalities bounce off of each other. It doesnāt really have stats - characters instead have ratings in āApproachesā, like Forceful, Flashy or Sneaky - and it doesnāt distinguish between physical and emotional injuries, so you wouldnāt need separate sets of traits for the investigative and courtroom bits.
For a rules-medium option, you might instead have a look at Skulduggery. Its primary conflict-resolution mechanism is arguing, to the extent that the rules for physical combat are considered optional, so courtroom drama is a natural fit. Plus, its temptation mechanics could be adapted to give mechanical weight to the sorts of eccentric personalities you run into in Ace Attorney. In a nutshell, each campaign has a defined set of opportunities to be terrible - which can range from stuff like Pride and Lust in grittier games, to stuff like Pedantry and Spite in lighter ones - that charaters must roll to resist whenever a clear opportunity to indulge them arises. Which means that in the right sort of game, you can totally stat up a character who has to save vs. nitpicking whenever people are wrong on their presence. A potential complication is that the gameās default assumption is that itās about awful people being awful to each other, so youāll need to keep a careful eye on how youāre statting things to make characters who arenāt total jerks work.
Now, if you wanted to go rules heavy, Ace Attorney basically views courtroom drama via the lens of shounen fight manga, so thereās part of me thatād be terribly tempted to do it as an extremely variant setting for Anima Prime. The manoeuvre/strike rhythm would be an excellent fit for the dynamics of the courtroom scenes. Of course, youād need to come up with a completely new list of skills and powers, which is why this last one isnāt a serious recommendation!