Given how few companies give interview feedback, I would predicted very little in the way of lawsuits involving that.
People can't "willfully or accidentally mis-interpret" what you don't say.
The real question is, "If people gave interview feedback, would they get sued for it?" I think so. Doubly so if the feedback was at odds with the candidate's self-image or if it is written. (It is a lot easier to file a lawsuit based on what was written to you than your memory of what was said.)
More importantly HR departments universally say so. And as long as HR departments say so, managers will follow their advice and not give interview feedback.
HR departments say so because if no one ever gives interview feedback, no one will ever get sued for giving the "wrong" feedback. They are like the legal department in that they will never look to help a company actively gain a competitive advantage, and certainly never to do the decent thing by people outside the company's management.
The real question is, "If people gave interview feedback, would they get sued for it?" I think so. Doubly so if the feedback was at odds with the candidate's self-image or if it is written. (It is a lot easier to file a lawsuit based on what was written to you than your memory of what was said.)
More importantly HR departments universally say so. And as long as HR departments say so, managers will follow their advice and not give interview feedback.