Who Played the Character of Andrew Laeddis in Shutter Island?

There is a scene in the film when Dicaprio, as Teddy Edwards, briefly talks to Andrew Laeddis. Laeddis is siiting in a chair. The same chair, next to the fireplace, that the German Dr was originally sitting in when we first meet that character. He looks a lot like Robert De Niro but apparently it is not him? I couldn't tell because he was covered in blood. And then suddenly becomes Chuck, mid lighting of Dicaprio's cigarette.