Alexander C. Furnas at the Legislative Branch Capacity Working Group:
The now famous Indivisible guide to grassroots activism advocates mass, coordinated constituent communication with members of Congress, among other tactics. Recent research has, however, shown mixed results regarding the effectiveness of such communications. Media surrounding Congress’s failure to repeal the Affordable Care Act or protect Net Neutrality has nonetheless highlighted the tactic as an integral form of Trump-era activism and unresponsive legislators have generated headlines, and hand-wringing. Often overlooked is the fact that these campaigns impose significant costs on the institution --- indeed, that is likely part of what may make them effective. Preliminary results from the Congressional Capacity Project suggest that even legislative staff within members’ personal offices often spend time dealing with constituent communication instead of focusing on their legislative responsibilities.
Mass constituent communication is often facilitated by interest groups organizing their members or subscribers to contact their representatives. These organizations lower the cost of communication by providing call scripts, email templates, or form letters. More recently, webapps like resistbot allow people to contact their representatives by SMS or chat. As technology has lowered the cost of communicating with members of Congress, the volume of constituent communication that offices receive has grown dramatically.