You may not be able to change their opinion nor their behavior... but you can still do right.
Now there was a man named Joseph, from the Jewish town of Arimathea. He was a member of the council, a good and righteous man, who had not consented to their decision and action; and he was looking for the kingdom of God. This man went to Pilate and asked for the body of Jesus. Then he took it down and wrapped it in a linen shroud and laid him in a tomb cut in stone, where no one had ever yet been laid. (Luke 23:50-53)