Is asking for a social media password any different to asking to read someone’s diary?

So…. employers in the US are asking job applicants for passwords to social media sites such as Facebook to enable them to “research” the employee before deciding whether to offer employment.  Tough call – provide the password and cross your fingers (even the most perfect applicant risks a connection to someone/something deemed undesirable) – refuse (in principle or out of fear) and be damned!  Trouble with social media is it blurs the boundaries.  It’s not a conversation in a pub, but often it is pub conversation  – and after one or two for the road at that!  Where does research become prying, screening become reading the diary, and qualifications and professionalism hostage to the fortunes of a group of disparate contacts who often have nothing more than their own self promotion at heart.