It's not opinion. It's what we have seen in Geass.
Lelouch completely deserved to die for Euphemia's death. Suzaku had every right to kill him.
But what did he do? He spared the bastard. Suzaku's too much a good guy, if you ask me.>>11598673
He did it because he was able to fulfill Euphemia's goal by turning him in. Like I said, Lelouch was a dead man at that point. Suzaku gave him another shot to live, for the sake of realizing Euphemia's goal. Too damn nice.