AC360 Preview: GOP senator says Obama violating War Powers Act

Editor’s note: Watch the interview with Sen. Paul here.

(CNN) - When we book guests on the show, we generally have a pretty good idea what they’re going to talk about. But every now and then, we get some surprises.

Today, a surprise came courtesy of Sen. Rand Paul, R-Kentucky.

We wanted to talk to him about the War Powers Act and whether the Obama administration was breaking that law by participating in the NATO strikes in Libya.

Sen. Paul has been pretty adamant about the administration’s failure to comply with the law, which says that if the president starts military action, he must seek congressional approval within 60 days, or the mission will have to stop. Congress was formally notified about the airstrikes in Libya on March 21. That means at the end of today, Obama’s 60 days are up.

“We need to have a debate and let the people decide. Before we send our young men and women to war, we need to have a debate in Congress. That's the way it should be, and I'm going to do everything I can to make it so,” the Kentucky lawmaker told Anderson Cooper in an interview set to air Friday on AC360°.

Paul points out that the administration took the time to get approval from the United Nations and the Arab League to intervene in Libya, but has yet to ask Congress for its stamp of approval.

But the interview took an unexpected turn when Cooper pressed Paul on Congress’ responsibilities. That’s when the new senator unleashed some pretty harsh words about members of the House and Senate – and admitted that he sometimes wants to return his paycheck. So there is clearly a lot of pent up frustration there.