Explain on what basis Lincoln and Johnson justified their assumptions

Explain on what basis Lincoln and Johnson justified their assumptions of Reconstruction policy and the basis on which Congress justified its takeover of Reconstruction.

What specific events moved Congress to take Reconstruction out of the hands of the president?

ANSWER
Lincoln’s and Johnson’s policies rested on the president’s power to pardon. To them, states had not legally seceded, individuals were guilty of treason. Congress’s policies were rooted in its authority to admit new states and guarantee each state a republican form of government. To Radicals in Congress, the southern states were “conquered territory.” Congress took control of Reconstruction because of the South’s lack of remorse evidenced by the passage of Black Codes, violence against freemen, and the election of former Confederates to office.