WASHINGTON, DC - JUNE 22: Facebook's Chief Operating Officer Sheryl Sandberg speaks with AEI president Arthur C. Brooks during a public conversation on Facebook's work on 'breakthrough innovations that seek to open up the world' at The American Enterprise Institute for Public Policy Research on June 22, 2016 in Washington, DC. (Photo by Allison Shelley/Getty Images)

WASHINGTON, DC - JUNE 22: Facebook's Chief Operating Officer Sheryl Sandberg poses for a photo with AEI president Arthur C. Brooks before a public conversation on Facebook's work on 'breakthrough innovations that seek to open up the world' at The American Enterprise Institute for Public Policy Research on June 22, 2016 in Washington, DC. (Photo by Allison Shelley/Getty Images)

WASHINGTON, DC - JUNE 22: Facebook's Chief Operating Officer Sheryl Sandberg speaks with AEI president Arthur C. Brooks during a public conversation on Facebook's work on 'breakthrough innovations that seek to open up the world' at The American Enterprise Institute for Public Policy Research on June 22, 2016 in Washington, DC. (Photo by Allison Shelley/Getty Images)

WASHINGTON, DC - JUNE 22: Facebook's Chief Operating Officer Sheryl Sandberg speaks with AEI president Arthur C. Brooks during a public conversation on Facebook's work on 'breakthrough innovations that seek to open up the world' at The American Enterprise Institute for Public Policy Research on June 22, 2016 in Washington, DC. (Photo by Allison Shelley/Getty Images)

This image courtesy of Democratic Rep. Elizabeth Esty's office shows Rep. Esty(2n-L) with Rep. John Lewis(C) and other members of Congress staging a sit-in on the floor of the US House of Representatives on June 22, 2016 in Washington, DC. US Democrats staged a rare sit-in Wednesday in the House of Representatives, demanding that the Republican-led body vote on gun-control legislation following the Orlando nightclub massacre."We have to occupy the floor of the House until there is action," Democratic Congressman John Lewis, a civil rights icon who marched with Reverend Martin Luther King Jr in the 1960s, said before he and dozens of colleagues sat down on the carpeted well of the chamber.The dramatic action came just as the House presiding officer moved to declare the body in recess. / AFP PHOTO / Rep. Elizabeth Esty / Handout / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO /CONGRESSWOMAN ELIZABETH ESTY" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS HANDOUT/AFP/Getty Images

WASHINGTON, DC - JUNE 22: Accompanied by House Minority Leader Rep. Nancy Pelosi (D-CA) (R), Democratic presidential candidate Hillary Clinton (L) leaves after meeting with House Democrats June 22, 2016 on Capitol Hill in Washington, DC. Clinton joined the House Democratic Caucus meeting as she continued to campaign for the election. (Photo by Alex Wong/Getty Images)

WASHINGTON, DC - JUNE 22: U.S. Sen. Christopher Murphy (D-CT) is interviewed by a reporter prior to his joinning in a sit-in with House Democrats June 22, 2016 at the Capitol in Washington, DC. House Democrats are staging a sit-in on the House floor to demand Speaker Rep. Paul Ryan (R-WI) not to recess the House without voting on legislation including the bipartisan ÔNo Fly, No BuyÕ legislation and a universal background check bill. (Photo by Alex Wong/Getty Images)

WASHINGTON, DC - JUNE 22: U.S. Sen. Christopher Murphy (D-CT) heads towards the House Chamber to participate in a sit-in with House Democrats after he was interviewed by a reporter June 22, 2016 at the Capitol in Washington, DC. House Democrats are staging a sit-in on the House floor to demand Speaker Rep. Paul Ryan (R-WI) not to recess the House without voting on legislation including the bipartisan ÔNo Fly, No BuyÕ legislation and a universal background check bill. (Photo by Alex Wong/Getty Images)