Yankee White - S1-E1
Corrected entry: Towards the end of the episode, when Gibbs and Todd leave the toilet cubicle, she tells him of the problem in the press section and starts towards it. He tells her to cover the president. He had no way of knowing that the Secret Service had left the President unprotected.
Correction: No he would not know, but he told Todd to cover the President so the President will have more protection other then the men that were already there.