The more I learn about Maryse the more I despise her. In this passage, Maryse outrightly admits that she was willing to attack the Downworlders when she thought she outnumbered them. Maryse is actually pissed that Luke didn’t make it even more easy for her to kill them all. Not only does it make her an unrepentant murderer, but a coward as well.
I also like to point out, Maryse had zero remorse whatsoever for the people that she had murdered. I said it back in ‘City Of Bones’, but I’m going to say it again: The Lightwoods only surrendered to the Clave because they had no other choice! She actually just confirmed that in this passage. Maryse (and most likely Robert) don’t feel that what they did was wrong. They are only angry at Valentine and Luke because they both got caught.
By this logic, The Lightwoods should be both in prison right now. However, it’s not a sane and just world, so basically the Lightwoods used their wealth and influence to get out of a possible life sentence.