Do you consider her to be one of the villains on the show ?

I think she's really a complex character. I mean she really thought that Assemblyman's career could help the police do a better job in the future right ? If so, lots of innocent would be spared a lot a grief and bad guys would be put in jail more easily, right ?

Put yourself in her shoes : if you think that one person is the only one who could help saving hundreds of people in the future : would you cover the crime of one of his family member ? One innocent sacrified in order to save thousands ?

What do you think ?

I remember liking her character a lot, despite everything. I could sense her humanity and it was clear enough that her motives were not your usual greed for power or money. Characters whose choices are driven by a "higher purpose" are always extremely complex and controversial, because they move in the realm of ethics, and because their motivations could be ours. 

This said, I personally consider the life of one single innocent person more precious than that of a thousand who could benefit from his/her death in the future. Unless that single person was me - in which case we might negotiate - I could never sacrifice a random person for a future which hasn't been written yet and of which we know nothing.
I think she's part of the evil ones before she was a chief but, had a change of heart? She's just playing it safe with the assemblyman maybe because she's afraid to die too? I personally think she's a good person, I mean shes been helping Daegu a lot and she cares about him. 

She isn't naive... She backed the wrong horse for the right reasons... But the wrong horse was already showing signs of being bad... She choose to ignore...

All her other actions are just back pedalling and covering her ass.