The Engine is not public, and the games are not true Point and click, but they are close, are the Ace Attorney series on GBA/Nintendo(3)DS

There are a few people that try to understand the scripting used for these games and it is quite interesting, and I think with a few changes could be easyly updated to a more classical P&C game. Two itteration of this licences are more close are the "Gyakuten Kenji" aka "Miles Edgeworth Investigation"

Here are some fan made tools to generates working scripts: