I'm sorry but you actually aren't being technical. When he grabbed him that was assault. A civil case. Since there are really no damages it won't go anywhere. Now, if you are talking about the punch in the face, then yes, that would be battery. However, the guy had no right to hold the door open and go inside. The old man made it very clear that he wanted him out of there. He was trespassing and the old man defended his property. COULD it have been battery? Yes, but was it with the old man's affirmative defense of defense of property? No. So TECHNICALLY, you are wrong.
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