Here's the thing, though: that doesn't mean your labor attorney is wrong. One employee says something to a rejected candidate that could be interpreted as labor discrimination, and it doesn't matter how rigorous your process is, you're still in for the cost and time of a lawsuit to prove it.
How do you build the 0.1% risk of a company-ending lawsuit into your business case?
I'm a very "right to work" (bullshit term I know) oriented person, in that I think neither companies nor their employees should be obligated to each other at all. Firing/quitting should be frictionless and easy. Instead, firing is wraught with legal problems such that you can't even fire an employee unless you can monetarily justify the cost of a lawsuit against their impact of being a negative influence, or they're part of some indiscriminate layoff procedure.
If I'm quitting or changing jobs, I'm harangued about it left and right by managers as to why or how this could happen.
Let's not pretend we owe each other anything and just move on like any other business transaction.
When we spoke to a labor attorney about this awhile back, their first reaction was basically that we would be insane to do it, because of the legal liability.
We got comfortable with the idea of feedback because we think that we have a clear, documented process that stands up to scrutiny. However, I think for many employers, recruiting decisions ARE arbitrary and unfair. Honest feedback would merely expose the decisions for what they are - reliant on personal affinity with candidates, vague notions of "culture fit", and gut decisions. There's very little quality training for how to ask good questions, evaluate those responses, and render a hiring decision. If candidates could actually hear the hiring manager and recruiter's thoughts, they'd rightfully be pretty angry.