President Obama isn’t the first to make signing statements. President Reagan used them. Personally? I think they’re unconstitutional. Nothing in the US Constitution gives a president the right to reject portions of bills. He can either sign or veto them. He has no constitutional right to modify or ignore them.
That aside, I’m saying a law that prevents or limits a president’s right to advocate (to Congress) for particular legislation is also unconstitutional. Congress has no right to tell the president what topics he is permitted or not permitted to discuss with Congress.
Again, I know the administration is pushing a very fine line here, but frankly, he knows he can get away with it. There are limits, but it’s very difficult to tailor legislation precisely enough to excise what one wants. Even then, there’s no way to resolve disagreements short of impeachment or tying the issue up in courts for years.
Congress is at fault for creating an overpowerful executive branch in the first place. The chief executive is well, well beyond commander in chief and head diplomat these days.
“He has no constitutional right to modify or ignore them.”
I think that depends. If congress writes a law that says “imprison everyone who looks cross-eyed”, the next president is free to ignore it and pardon those convicted under it much like Jefferson did with the Alien and Sedition Acts. On the other hand if the president wakes up tomorrow and decides to imprison everyone who looks cross-eyed then that is clearly unconstitutional.
In short making laws is unconstitutional but ignoring laws is not.