I was going to start a thread about this two weeks ago.
My mate works at a company, hates the dept he's in so applied for another dept and he was given the job depending on references.
The stupid bugger then gave his notice in because he was sure he wouldn't have a problem.
The Manager of the new job rang him and told him because of a bad reference she couldn't employ him and now he's without a job.
He contacted his HR 3 times but they said they can't tell him what's on the bad reference or who gave it and the Manager of the job he was hoping to get doesn't know either just that she was told not to employ him
I thought this was complete BS until I asked my boss who is an employment law expert who goes to tribunals a lot and he confirmed it.
The easy way around this is to pose as an employer and ask for a reference for yourself.