While states are responsible for drawing congressional districts every ten years, Congress has the power under the Constitution’s Elections Clause (Art. I, sec. 4) to set rules governing how districts are drawn. It’s used this power in the past, for example, to mandate that states use single-member districts.
Most current efforts to reform congressional redistricting are taking place in the states. But at least some members of Congress also are proposing federal reforms. Here’s a rundown of the redistricting reform bills that have been filed in Congress as of May 12, 2017.