Law questions: constitutional separation of powers?

The President and Congress are both duty-bound to stay within the powers the Consttution enumerates to them. That's not to say that some implied things may arise which are not totally clear and then that's when the Supreme Court has to come into action to define how the act is applied, since the Constitutio was written long ago and is subject to interpretation to modern questions. Legislative histories are doents on file which list and describe congressional actions day-to-day, such as the Congressional Record. Signing statements are the current actions before the current congress