It is the duty of an attorney and counselor: (1) To maintain the respect due to the courts of justice and to judicial officers; (2) to counsel or maintain no other actions, proceedings or defenses than those which appear to him legal and just, except the defense of a person charged with a public offense; (3) to employ, for the purpose of maintaining the cause confided to him, such means only as are consistent with the truth; (4) to maintain inviolate the confidence, and, at any peril to himself, to preserve the secrets of his clients; (5) to abstain from all offensive practices and to advise no fact prejudicial to the honor or reputation of a party or witness, unless required by the justice of the cause with which he is charged; (6) not to encourage the commencement or continuance of an action or proceeding from any motive of passion or interest.