This post has been updated to reflect the fact that Sen. Rand Paul will not be testifying at today’s hearing, due to scheduling conflicts that arose from the hearing's time change. It is now scheduled take place at 4:00 p.m. EDT. Click here for a full list of the witnesses who will be testifying.

When Sen. Rand Paul (R-Ky.) courageously held the Senate floor for 13 hours in an historic filibuster to put a spotlight on a vast killing program run out of the White House - which has left 4,700 people dead, including four American citizens - there was a groundswell of Americans saying that they would “Stand With Rand.” If Paul was committed enough to filibuster, they were committed enough to stand with him.

Today, there will be another history-making moment. Sen. Dick Durbin (D-Ill.), who is a longtime champion of the Constitution and human rights, will be chairing the first-ever hearing in the Senate focused on drones and the killing program. Today’s hearing presents us with an opportunity to stand with Dick for what is right.

Over the past five years, the White House has led a vast killing program that has used drones and other weapons to kill people, often far from any battlefield, based solely on the say-so of the president or what a government memo calls an “informed, high-level official.” Congress never authorized the killing program. The legal memos that purport to justify it are hidden from the American people, and the administration refuses to answer even the most basic of questions: in what countries has the killing program been used?

Don’t the American people have the right to know where the White House might end up starting a war that we might not be able to get out of? Or who the White House thinks is the enemy and how the executive branch decides - on its own - who lives and who dies? Or why the White House thinks the program is legal?

Our country just got out of nearly a decade of war in Iraq, and President Obama is working to get the country out of nearly 12 years of war in Afghanistan. But without even a single congressional hearing, and certainly no declaration of war, the administration is on its own, pulling the United States into fights in other parts of the world, with no end in sight—and without a public explanation of who it is killing and why.

We live in a country that is based on the Constitution’s system of checks and balances, as well as the rule of law. The hearing on Tuesday could be the start of the Senate reasserting its role under the Constitution’s separation of powers - and a chance to make clear that America is a country that complies with the law. We are grateful to Durbin for holding the hearing, and grateful to Paul for being the lead witness.

There are two ways you can participate. If you are lucky to live close to Washington, DC, then come in person. But before you do, fill out this form so that the Senate Judiciary Committee can try to get a room that is big enough to fit all of us. And if you can’t make it in person, you can watch the video feed here. And don’t forget to let your senators know that you are watching.

So, Tuesday at 4:00 EDT—Join us at this key hearing!

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