Democrats on the Senate Homeland Security and Governmental Affairs Committee are urging Chairman Ron Johnson, R-Wis., to hold a hearing on the census in the wake of the Trump administration’s decision to add a citizenship question.

Sens. Claire McCaskill, D-Mo., Kamala Harris, D-Calif., Tom Carper, D-Del., and Gary Peters, D-Mich., sent a letter to Johnson on Friday asking him to schedule a hearing “at the soonest time possible.”