You may have a fake identity, but only to be safe and not to commit any felonies. This can be used to escape criminals who hunt you down. The police will have a record linking the fake identity to the real one. You have to register to get a fake identity. The reason why is so that if you escape a criminal charge, the police can find you with your fake identity. The records are not to be shared with anyone other than other police officers, so they can arrest the person if needed.