Daniel Solove comments on USA Today article about financial institutions culling from public records databases to arrive at identifying facts, rather than using Social Security Numbers:

Concurring Opinions: Verifying Identity: From One Foolish Way to Another:

The problem with using this method is that the information in public databases is often riddled with errors. Why do banks need to go behind your back to snoop out information about you? Banks and financial institutions already have a relationship with you -- after all, you established an account with them. They can use some of the information they gathered at that time to establish your identity and then ask you to supply additional information to help identify you. But going behind people's backs and trolling public records for data does not strike me as a particularly effective method given the possibility for errors in those records.

Anyone who has had someone else's information in a credit reports know that matching records, even when there is a solid, government-issued identifier, seems impossible on the scale that's required for the credit agencies. These public records databases often work with pieces of data that aren't tied to a unique identifier like a SSN. Imagine the torture of trying to get access to your money -- or get a new credit card -- when your financial institution is using data that is, often at best, tenuously matched.