> Agreed. What are the questions you ask to determine their detective abilities?

in my experience, talking to a candidate across a couple of rounds and asking some generic question that can create discussions, will get some answers. sometimes, designing a system together can help a lot (as always reminding the candidate that there are no wrong answers).

at the end of the day, interviewing is a flawed process and you will get it wrong -- the question i don't see being asked is: what do you do if you get wrong?

Own up to it and give a healthy severance as quickly as you can.