Pakistan Legal Practitioners and Bar Councils Rules, 1976 — section 170

170. An advocate must decline to conduct a civil cause or to make a defence when convinced that it is intended merely to harass or to injure the opposite party or to work any oppression or wrong. But otherwise it is his right, and having accepted a retainer, it becomes his duty to insist upon the judgment of the Court as to the legal merits of his client's claim. His appearance in Court should be deemed equivalent to an assertion on his honour that in his opinion his client's case is one proper for judicial determination.