If you catch someone in the act of robbing your house but he/she is unarmed, can you legally harm him/her?

Call the police first. They have a much better chance than you of catching and subduing the robber. A retired cop told me that a homeowner should not shoot a robber in the front yard and if the homeowner does shoot a guy in the yard, that he should drag the body inside the house. I think that officer was joking because he added that if you drag a body into a house, there will be a blood trail