A lawyer cannot knowingly allow or encourage a defendant to commit perjury by lying on the stand. However, can they encourage a lie by omission?
So for an example If I tell the police that I didn't have any blackmail material on some person when they asked me if I committed blackmail, but neglect to point out I still blackmailed them by bluffing them into believing I possessed the material. Or claiming I don't have a copy of some information their looking for but withholding the fact that's because I gave the information to a friend to hold for me etc.
Can a lawyer encourage these sort of misleading, but technically true, answers with the explicit intent of trying to mislead investigators, or jurors, into making a presumption they know isn't true? Would a lawyer encouraging this sort of behavior risk either legal sanctions or disbarment if it was known they were doing it?