I'm not sure the content of the pictures actually matters from a legal perspective, unless the acts portrayed in the photos would be considered illegal. In terms of ownership of the photos, I think it depends on whether you make a profit from their distribution or not. If you sold the photos to a publisher, or put them on a pay to view internet site, then you may owe part of the profits to the subject of the photos unless they have otherwise signed a waiver giving up their right to compensation. If you just pass out the photos to people for free, plaster them in the locker room, or hand them to the other party's boss, then while that may be a sleazy thing to do, I'm not sure there's much anyone can do about it as long as you shared the photos for free. I'm not totally sure about this though. There still may be something that can be done, for instance, if the person loses their job as a result and sues for damages due to the malicious action.