It's a Western I saw at school, I just remember one scene..
There is a Native American camp, I'm pretty sure they were prisoners.
One of the Indians has made a crime (probably stole something, I'm not sure).
The guard (while on a horse (?)) asks who is the guilty. Nobody answers. The guard then threatens the whole camp: if the guilty doesn't come up, everybody in the camp will be punished.
Does anyone remember this movie?
Thanks in advance!