Exacerbating the problem of using the Social Security number as an identifier is the fact that the Social Security card contains no biometric identifiers of any sort, making it essentially impossible to tell whether a person using a certain SSN truly belongs to someone without relying on other documentation (which may itself have been falsely procured through use of the fraudulent SSN). Congress has proposed federal laws that restrict the use of SSNs for identification and bans their use for a number of commercial purposes—e.g., rental applications.[26]