Getting back to your original question, I think we get to the question of what you are going to do when you find out who it is that is stealing your mail? I hope it isn't your neighbor, because if it is and you do something, then life just gets a bit suckier. If you are worried about them stealing your mail, I would do something else then confront them and cause more friction. The cops are not going to do anything. You'll just have to worry about parking your car in front of your home at night or every time you leave the house what you will find when you get back. Think it over. Slime is slime and if they really are scared of you, they will just find a way to get back at you without you being able to do anything. Sliced tires, a rock through your front window, my brother-in-law even had someone pull up to his home and shoot his dog at night. A locked box might be a whole lot less trouble.