As usual, the article is full of BS. There are no "missions" where the object is to beat up prostitutes (that I can recall anyway). That picture that is supposedly a "scene" from the game is not, in fact, a scene from the game. It's a piece of artwork from the game perhaps (I don't recall that particular one but I didn't play GTAIV really heavily).
Also, anyone with half a brain can tell just from looking at the picture of that kid that his issues with violence and women probably stem from a lot more than playing a video game.
Then there's the prosecutor blaming the video game. Hey, Mr. Lawyer Man. Ever heard of a little thing called personal responsibility? As in, maybe he should be held accountable since he's the one who committed the crimes? Lots, and lots, of people (such as myself) have played GTAIV and, in fact, did not go out and sexually assault women. Suggesting that this kid would have lead a perfectly healthy, crime-free life if he hadn't played GTAIV is stupid, preposterous, and downright foolish.