• by Wendy Davis  @wendyndavis, February 3, 2011

Facebook recently sparked a wave of criticism when it announced in a blog post that it would allow developers to start accessing users' phone numbers and addresses. The social networking service backtracked within days and suspended the plan pending potential modifications.

Now, Reps. Ed Markey (D-Mass.) and Joe Barton (R-Texas), co-chairs of the House Bipartisan Privacy Caucus, are seeking answers from Facebook about its initiative. The lawmakers sent CEO Mark Zuckerberg a letter this week posing a host of questions, including whether the company revealed any users' phone numbers or addresses to developers, whether Facebook believes that announcing this type of plan via a blog post adequately notifies users about the feature, and whether the company considered whether the new initiative would pose any special risks to children and teens.

The lawmakers also are asking for details about why Facebook suspended the feature's launch and what changes are in the works.

One of the major criticisms of Facebook's plan stemmed from the procedure it intended to deploy to secure users' consent. The company said that it planned to show users a screen asking them if they want to grant developers permission to access contact information.

But many observers predicted that users would go through the process too quickly to realize that they were allowing third parties to access their contact information. In addition, users who would have declined to share their data with developers apparently wouldn't have been able to download the apps.

Security firm Sophos -- which was among the earliest critics of Facebook's proposal -- warned against sharing contact data with app developers. "Shady app developers will find it easier than ever before to gather even more personal information from users," the company said. "You can imagine, for instance, that bad guys could set up a rogue app that collects mobile phone numbers and then uses that information for the purposes of SMS spamming or sells the data to cold-calling companies."