> With that in mind, the best way to deal with these situations is openly and transparently. Once the you become aware of the conflict between hiring the superstar employee and double-crossing your valued friend, you should get the issue onto the table by informing the employee that you have an important business relationship with his existing company and you will have to complete a reference check with the CEO prior to extending the offer. Let him know that if he does not want that to happen, then you will stop the process now and keep the process to date confidential. By speaking with your friend before making the hire, you will be able to better judge the relationship impact of hiring her employee. In addition, you may avoid making a bad hire as often candidates who do well in interviews turn out to be bad employees.
I'm not sure "open and transparent" is how I'd describe that.