Problem with the ending.
They should NOT have been in jail. They did not really commit any crimes. Everyone they killed was self defense and they HELPED catch the real criminals. All they wanted was their cat back. They were so obviously NOT real criminals. No criminal charges should have been pressed against them and if I was the governor in the fictional universe of this movie I would have pardoned them.
I think they got only a six month sentence but the criminal record will have lasting effects. Harder to get employment and if its felony they cannot vote (you do NOT lose voting rights for misdemeanor, not sure which one it was).
I honestly cannot think of any actual crime they committed, it seems like every act that would normally be illegal would be covered by extenuating circumstances.