Senator Al Franken of Minnesota sent a letter to Niantic Chief Executive John Hanke asking what user data Pokemon GO collects, how the data is used and with what third party service providers that data may be shared.
Basically, if you log into Pokemon Go through your Google account on an iPhone - which is the first option provided -- it gives "full access" to your account. According to Google's help page, that should only be "granted to applications you fully trust."
The National Highway Traffic Safety Administration said in March it was collecting information after a Google self-driving car struck a municipal bus in California in a minor crash. But it did not open a formal probe.