I applied to Intergraph once, and they wanted me to sign a release for a consumer profile report. I wrote onto the form that they had to give me a complete copy of the report, struck out a few objectionable lines, initialed the changes, and signed the form.
They immediately ended the interview process. They could not give me a copy of any portion of the report due to "confidentiality agreements".
I deciphered that as they were using information to discriminate between qualified candidates that is at best shocking to the conscience, and at worst blatantly illegal.
You cannot know if the company is breaking the law if they rigorously suppress any evidence of it.
I have some experience with background checks, since I ran a consulting firm and had major financial firms as clients, all of which do this kind of background checking, and while I don't think it's at all unreasonable to withdraw from consideration over credit checking (I would too), I think you probably overreacted --- because it is in fact true that you're contractually not allowed to share background check reports with their subjects.
That seems like a convenient way to get away with libel. My real name is so common that every state likely has a person with the same name and surname with a criminal record. There was another person with my name at my high school. There is another person with my name at my current employer. In the past, there were three people with my name in the corporate email directory.
With credit reporting, if a company gives you less than their best offer as a result of derogatory information on your credit report, they are obligated to furnish you with a copy of it at their expense.
So you might understand why I might like to know if a company is passing me over for consideration because of information given them by a third party that I cannot see, verify, or rebut. I have zero faith that companies that perform background checks never make mistakes.
That confidentiality clause for background check reports is ethically similar (but less vile) to a clause in a murder contract that requires the payer and the murderer to keep the existence of the contract secret from everyone, particularly the intended victim. You can't contract your way out of culpability for libel.
Besides that, they were the ones that told me to go pound sand just because I wouldn't give them carte blanche permission to investigate me.
I'm not saying you should be OK with background checks.
I'm saying that they're commonly used, especially in the financial industry (for regulatory reasons), and that the people who procure them really are (at least, often) prohibited from publishing the results.
I was background checked almost a dozen times at Matasano and never once got to see a report.
You're totally within your rights to be irritated by these checks. I'd refuse many of them too! But I think your argument about why you didn't get to see your report is overdetermined.
It may contain potentially non-factual statements that may be sufficiently derogatory to cause harm to my reputation and livelihood. I consider the attempts to keep it a secret to be an attempt to evade accountability for incorrect reporting.
I trust the HR departments of most employers and the background check companies to act ethically about as far as I can kick Jupiter with my bare feet. Which is zero meters. I trust them zero. None.
If I cannot see what they are doing behind my back, I naturally assume that they are discriminating on the base of race, age, sex, religion, family relationships, sexual orientation, hairstyle, and shoe quality, while cramming every rejected candidate into either "unqualified" or "bad cultural fit" piles, for plausible deniability.
I understand the need for background checking. But I have also been cleared by the US federal government, and they have a process for handling derogatory reports that would allow someone who might be negatively impacted to speak before a federal judge. If there was ever a problem with a government background check, the person affected always got to see what it was, and rebut or appeal through an established process.
If a private background check says I not only eat babies, but do it in a racist and fiscally irresponsible way, I can't tell whether the company cuts off contact and never communicates with me again because of that report, or because it is just a company that does that in general.
My opinion is that you are insufficiently suspicious and overly trusting of the companies buying and selling private background checks.
Besides all that, I would wager a trivial amount on the hypothesis that many companies that pull background checks do so to learn spending habits and salary history, so they can initially offer the candidate the lowest salary they would likely accept.