I think the Chofetz Chaim writes that one should not start a topic that can likely LEAD to issues of Lashon Hara. In my humblekite I would think kny is correct.
Of course we have the ever vigilant, untiring MODs who would NEVER let the conversation steer near those dangerous areas of lashon hara, but I think one must not even start such a conversation. -my humble opinion.