Damn, it would have been awesome to have him in the game.  This is the reason why:
 
" ...because Phoenix Wright only has one move, 'Objection!', we struggled. We designed a move for him: when he says objection, the actual writing attacks the opponent. However, 'objection' in Japanese is 'igiari' -- it's four characters, whereas 'objection' becomes ten. When we localise, the balance of the game gets destroyed because the move becomes bigger. There'd be no way of avoiding it! We had to remove him for these reasons. In the future, it is one of our aims to get him in."
 
Bummer.  I would love to jump all over the screen yelling "OBJECTION!" and kill someone.  He could have used his spiky hair as a weapon to.  Anyways, click the link for the full article.
 
Destructoid Link