I like the way you think, this is the first image that came to my mind.
I remember the media campaign stoking "world-wide outrage" following the publication of that Vietnam-era photo. I couldn't understand it, myself. But it was the Abu Ghraib of its time.
Playing devil's advocate for a second.........
Why kill this guy right away?
Under questioning would he lead us to bigger terrorists? (Like the ones that gave him the explosives.)
Is he being blackmailed? (How do we know other terrorists don't have his family and are holding them and they told him to plant this or else?)
So why is he suspected when they caught him red-handed? A bullet to the head is too quick. String him up and let him strangle slowly. When he names a valid accompolice, cut him down. Repeat process daily until he runs out of accomplices. On that day, forget to cut him down.