The Justice Shield is treasure that can be obtained in the episode Braverobber in Sly Cooper: Age of Thieves. It is worth 267 coins and the time needed to reach the safehouse is twenty-nine seconds.
"This mighty shield is greatly cherished by the Cooper Clan for being one of the many shields used by the famous Sir Galleth Cooper. This one was used to help him combat and defeat a three-headed dragon that lived in a cave. Well, that's what the legends say..."
It is located on a small boat that has been adrift on the middle of the loch. Sly's Wizard Costume is needed to get to this treasure.