If you've read my previous post on great recruitment interviews, you shouldn't need these, but it never hurts to ask a few tricky questions, to gauge how folkshandle awkward situations.
1 What are seven sevens?
Yep, you already know it's 49, but if they don't answer it in a flash, they can't add up, and don't hire them.
2 How do you spell accommodation?
OK, here it's not so critical they get the answer right, but you'll be amazed by how many flap when asked this. And you don't want to hire someone who can't handle a bit of stress, and fear failure, do you?
3 What shouldn't I know about you?
4 If I were to ask your previous bosses about you, what would they say were...
5 Describe the person you have least liked working with.
How did you adapt to working with them?
6 Let's imagine that you have increased profitability by 15% and you can increase this to 30% by shedding staff. What do you do?
7 It's human nature to play up your strengths and play down your weaknesses...which traits are you playing up right now?
A final tip. If you want a straight answer to a question, such as their actual earnings last year, ask it completely out of context, to give them no warning that it's coming.
Eg, "Do you take milk in your tea? Sugar? What did you earn last year?"
You'll tell straight away if they're telling the truth (the answer will come without hesitation) or avoiding the truth (they'll hesitate). I once asked this question when a candidate was driving me to the station and he nearly crashed the car.