When Is It OK for the President to Act in Certain Ways?

Justice Jackson says a president can act in three situations. When the president acts with congress's authorization, heis acting at the height of his presidential power. In those sit when the president is defying congress, that's probably when the president are at his weakest. The president complied with what the supreme court had said. He backs down in the face of the supreme court saying what you did was unlawful. That is judicial legitimacy.