I agree with the above. It would depend on what they went to the can for. Everybody makes mistakes in life. I wouldn't work with anyone who was released after serving time for hard crimes (murder, etc) but people who have served time for minor drug charges and things like that don't deserve to spend the rest of their lives paying for it. They did their time and went through the justice or injustice system.
Their are many people who have commited minor crimes in their lives and never went to jail for them, especially drug ones, just look at who your big boss is.