Unfortunately, people search sites are legal in the US. The information they provide is typically collected from publicly available records, be it voter registration records, court records, or marriage or divorce records. It should be noted however that the Fair Credit Reporting Act imposes regulations on how certain data such as credit histories can be used. ID True isn’t FCRA-compliant and, as such, can’t be used for purposes such as credit checks.
Upon searching for a person’s information on ID True, the site issues a reminder not to use this information to stalk or harass anyone. However, it’s hardly an effective deterrent and sites such as this can certainly be used for nefarious purposes.