You only fight to defend yourself or those in your care, using only as much force as necessary (no pre-emptive strikes allowed!). You must do your best to discourage others from starting fights.
If the vision or combat penalty for poor lighting is between -1 and -4 for most people, your penalty is the worse of double the usual penalty or -3. If the usual penalty is -5 or worse, you function as though you were completely blind. If you have Acute Vision, it only applies in situations with no darkness penalty.
