Last Shabbos it was raining in my neighborhood and I brought my rain coat (a shayne coat) with my name in it to shul. For some reason when I left shul, I didn’t look at the name tag and took a coat that I thought was mine. However, it turns out that I took a neighbor’s rain coat which had his name in it. And he walked home in the rain without a coat. I felt very bad that I took his coat and he got wet because of me. Was he allowed to take my coat home? I think this might be dependent if we hold like the Shach. Is there more of a sevara to say that he could have taken it because the shayne coats are more or less universally the same? Thanks for all the great work that you do.
He was right that he didn’t take yours. The Shulchan Aruch speaks about this case and he says that if things got mixed up in shul that we may not take the other persons home. The reason is that although he took yours by mistake, he may still not want that his should be used by you. Therefore the fact that they are the same will not help us here. This applies to a person that you don’t know. However in your case if you know the person enough that you can readily assume that he would agree that you take his coat home with you, especially since it stands to reason that he would want you to borrow it, to rectify his taking your coat. Then we could rely on the shach.
CH:M 136- 2 ,Aruch Hashulchan ibid 2.