Originally posted by Inhuman
Gamora was even above the common criminal in the prison. They all hated her. It was established she was a murderer and ran with galactic villains. We see Groot kill multiple people in the film.
I'm pretty sure Gamora was hated in prison because of her association to Ronan and something about many of the prisoners (eg Draxx) having lost family at Ronan's hands. Rocket said something specifically to that nature, could find the quote.
As far as Groot killing, he only killed bad guys, the blue skinned would-be buttrapist in prison only got his nosed/brain picked, but survived.
Seems this is one time Marvel didn't copy DC.
edit: I think every death at the hands of one of the GotG crew was a "bad guy".