In the mean time a member came up with a great idea. When a thief fails in his attempt to steal points he goes to jail. This jail is visible for all and you will see an image of a police cell with in it...the avatars from the thief(s). These avatars could be reduced 50% in size for example. The prisoners can't post & reply for a period of time which can be altered in de adminCP.

Members can buy then a 'escape from jail' or 'free prisoner'.