The "mob" you referred to in your previous message on this point. You were insinuating Mafia, but the "mob" in this context is the criminals, which is what you claim the Confederates were.
So why would the President turn someone over to criminals? How is that legal?
So you again admit Confederates were nothing but a lawless mob?
That's fine, I have no problem with it.
As for prisoner exchanges during wartime, those are entirely common and lawful.
If you think Lincoln gave away too much, then you might contemplate the recent exchange of Sgt. Bergdahl for, was it, five terrorist leaders?
Vallandigham & Bergdahl: