I was thinking of her as an example of What is "Human?", she'd be created by an alien device which the government found and is using.

They have the origional and she's only identical on a genetic level, she's a former Science Teacher who taught at a Mid-west Highschool not a soldier which is what the device turns out. Because it makes clones of the teacher the government claims that they don't have anymore rights than a car or toaster. They send her in to do Bomb Disposal or infected locations, Irraidated locations any place where risking an actual person isn't safe; they do it because they know in seconds she'll be replaced by an identical copy.

For the Justice League she could be a Government observer who's treated as if she's disposable by her superior


Then again it was only spitballing