Social media is a powerful and useful tool for facilitating communication between federal agencies and their constituents. However, the recent ruling by the Government Accountability Office (“GAO”) that a social media campaign undertaken by the Environmental Protection Agency (“EPA”) violated both the Federal Antideficiency Act (“FADA”) and the prohibition on grass-roots lobbying has raised questions regarding how agencies can continue to utilize social media going forward without committing similar infractions. The EPA’s campaign, which it undertook to promote its controversial Waters of the United States rule, was primarily conducted via the social media platforms Twitter and Thunderclap. These platforms provide a particularly effective means through which agencies can interact with members of the public. A clearer standard regarding what constitutes good practice versus what behaviors are disallowed needs to be determined in the interest of encouraging this valuable means of civil engagement.