To be honest, executing them here is probably a lot more merciful then what's awaiting them. ^^; The wait to be executed, I mean. Since they're... murderers who've tortured civilians for the sake of getting bait, and killed soldiers. They're getting executed no matter what.

Though it's also likely they're disarmed and chained up to be marched home as I'd rather not have the Iron Rose Knights perform executions anyway.