"broad daylight on the other side "
This could possibly refer to daylight showing through the holes the bullets made in the looter's body, emphasising the violence. This is unlikely to be literal; the man's body would be too mangled and bathed in blood.
Alternatively it suggests that the looter's life is ended and the "light" in his life is unreachable to anyone other than the soldier who fired the shot.
More likely is the insight that the soldier gained into what he had done, the moment after the shot. The 'broad daylight' is therefore a metaphor for self-knowledge and awareness of the implications of war.
A constructive suggestion is that it may refer to the saying, "to see the light on the other side". People who have reported near-death experiences have said that they have heightened awareness of God or salvation or visualise heaven or re-live important events in their life. The murdered looter may have had these experiences, but it may also refer to the soldier's heightened awareness of what he has done and how the rest of his life will change.