/summa/SS/SSII/SS_Q71:
We must now consider the injustice which takes place in judgment on the part of counsel, and under this head there are four points of inquiry:
(1) Whether an advocate is bound to defend the suits of the poor?
(2) Whether certain persons should be prohibited from exercising the office of advocate?
(3) Whether an advocate sins by defending an unjust cause?
(4) Whether he sins if he accept a fee for defending a suit?