I think there's a difference between bg check and references. Most companies I have talked to, don't extend offers till they verified references. But the bg checks happen after you sign an offer and there is a clause in the contract that if the checks come out to be bad, the offer can be rescinded. bg checks usually are just a check on criminal history and whether your past work experience is what you say it is. References are usually about whether their estimation of you and your skills match up with people who know you better.