Questioning Apple's privacy policies has become a bicameral proposition. Twenty-four hours after researchers provided a new open-source tool for iPhone users to view their phone's logged location history, Senator Al Franken (D-MN) and Representative Ed Markey (D-MA) have both issued sets of questions for Apple CEO Steve Jobs. While Franken's letter requests a "prompt" response, Markey wants answers "within fifteen business days."

Markey has long been a leading voice on tech questions, and has previously chaired key committees related to tech issues, so his letter was hardly a surprise. Indeed, in June 2010, Markey co-authored another set of questions for Steve Jobs on the issues of privacy and location-based services.

Apple's response last summer (PDF) went into considerable detail about how Apple generates and handles such information. Apple describes how, if location-based services are on, the iPhone will collect both cell tower and WiFi network data, collate it into a batch file, encrypt it, and send it to Apple over a WiFi connection every 12 hours. This helps Apple build its own location database to resolve or refine location requests when GPS is not available.

Apple notes that customers can always turn off "all location-based service capabilities with a single 'On/Off' toggle switch If customers toggle the switch to 'Off,' they may not use location-based services, and no location-based information will be collected."

Markey's new letter (PDF) asks many of the same questions his old letter did, including one about whether Apple complies with Section 222 of the Communications Act, which "requires express prior customer authorization for the use, disclosure of, or access to the customer's location information for commercial purposes."

Apple responded to this issue last year, saying that Apple is not subject to Section 222 but that "the privacy protections described in detail in this letter are consistent with the intent of Section 222."

Markey also wants to know if iPhone users can really disable the cell tower and WiFi logging, and he follows Franken's lead in asking about widespread use of iPhone and iPads by minors. "Is Apple concerned that the wide array of precise location data logged by these devices can be used to track minors, exposing them to potential harm?" he asks.