Facebook is constantly making tweaks to its privacy settings, with limited success. With the addition of a new privacy expert in its Washington office and two recent waves of changes to user controls for sharing, the network appears to be looking more closely at privacy issues.

On Tuesday, the company announced a few new privacy features that emulate the Google+ model of sharing — new features to friends lists that make it easier for users to sort friends into different privacy levels and share content with selective groups.

The optional features include smart lists, which automatically group a users’ friends into work, school, family and location-based groups, which can be edited by the user.

The changes come shortly after Facebook introduced “tag approvals,” which allow users to accept or reject photos before the information shows up on their profiles. At that time, the social network also made it easier for users to see how others view their profiles, and it added more basic privacy filters so that users could choose whether to post something publicly straight from a post.

Facebook has been the subject of a lot of scrutiny from Congress and privacy experts, who have raised objections about how the company collects data, what data it collects and how it notifies users about data collection.