Why can the US president meddle with the sentence of a convict? Isn't that against the separation of powers? Not that I have anything against this guy Manning in particular, just asking why is this "tolerable" in a democracy. Isn't it a risk, that the president can pardon whoever he wants?
"The President...shall have Power to grant Reprieves and Pardons for Offences against the United States, except in Cases of Impeachment."
Article II, Section 2