The groups, which include the National Election Defense Coalition, Electronic Privacy Information Center, R Street Institute and Public Citizen, asked the House Administration Committee and the Senate Rules and Administration Committee in a letter to schedule election security hearings that include testimony from voting machine vendors and election security experts.

“The security of our nation’s elections is acutely dependent on the vendors that supply our computerized voting systems,” the groups wrote. “The voting system vendors have operated with little oversight and no regulation for decades.”

“Given the gravity and urgency of this issue, we write to you to urge the committees to hold a hearing on election system security featuring sworn testimony from officers of the voting system vendors to shed more light on their practices which directly impact the security of the nation,” they added.