From what I read in the newspapers, that protection doesn't work very well in practice. In other words, the consumer ends up with the burden of proof to show the errors were indeed errors.
In real life, there can be gray areas. For instance, suppose you have an obligation but the company screws up your address and you never get a bill. They never get paid. (This has happened to me.) Since they never were paid, they blackmark you. I had a heck of a time proving it was their error (they left my apt # off the address and the post office returned it); further, they claimed it was still my responsibility to get them payment no matter what. I got it cleared up, but it was very aggravating.
For victims of identity theft or outright fraud, it seems the companies take their time investigating the problem, in the mean time, the blackmarks are on your record. It seems victims have to hire a lawyer to push the companies to correct theft/fraud errors. (I can understand a credit company not wanting to writeoff thousands of dollars of fraud charges, but that's shouldn't be the consumer's problem.)
When I got my credit report, I discovered a lot of junk in it -- long closed accounts listed as active or not responsive, stores long out of business, bad addresses, etc. For instance, I had a card with a store that closed. Unbeknowst to me, the successor store opened a new account for me, but had my address badly wrong so I never knew an account was out there. There were no charges, but still lots of bookeeping activity. This was frightening since it showed how easily errors can creep in or valid cards mailed to wrong places.