Two crucial elements of meaningful discourse that many people often overlook or miss entirely:
1) Always speak the truth, especially when addressing those in positions of power and authority. It is vital to be honest and courageous in confronting power with truth.
2) Avoid punching down or attacking those who are less powerful or more vulnerable; instead, direct your criticism and challenges upward toward those who hold greater power and influence.
There is a clear and intentional pattern here for a very good reason. As an additional aside, concentrate your efforts on educating and encouraging the powerful to respect and leave the common people in peace, because those in power are more frequently the ones who act immorally or unjustly.