It can't be completely wrong if you're not defending them, it has to be at the very least partially right.
Anyway, can I just be made understand your position please?
Hypothetically speaking; 2 gangs of people have a fight and one person is very seriously injured. You cannot know who did what to who but you know you have all the people who were all in the fight. Would you let them all off, or lock them all up on the evidence that you have?