Derb, the key difference in the two situations, and the reason that they most certainly are not the “converse” of each other, is the concept of “waiver” in connection with constitutional rights.
The right to trial is of constitutional dimension, and it is the default assumption of the system. Thus, a defendant must waive his right to a trial in order to plead guilty. By contrast, there is no constitutional right to plead guilty. (Indeed, in today’s column, I briefly discuss the fact that, in death penalty cases under the Uniform Code of Military Justice, a member of the armed forces is not permitted to plead guilty — the prosecutor must prove the case even if a soldier wants to plead guilty.) If a defendant does not plead guilty, the judge is not required to do the same sort of searching inquiry that the rules require for a guilty plea. The case simply proceeds to trial.
The searching inquiry in a guilty plea hearing is required because the law says that waivers of constitutional rights must be “knowing and voluntary.” This is a fixed target for a defendant who wants to get out of his guilty plea. If he can show that the legal advice he got was so bad the plea could not possibly have been knowing and voluntary (e.g., counsel didn’t inform him of the charges against him, counsel threatened him that he had to plead guilty), the plea will be vacated and he gets to have his trial — which is the guarantee the system gives him in the first place. It doesn’t really matter if the evidence against him was overwhelming; the plea is illegitimate.
On the other hand, if the defendant has gotten his trial, he is in a much different posture. He has no faulty waiver to shoot at. He is stuck, instead, with trying — against the context of a full trial — to satisfy the daunting test for ineffective assistance of counsel: (a) that his lawyer’s performance fell below an objective standard of reasonableness (which the cases construe very generously for lawyers), and (b) that this dereliction actually made a difference in the outcome of the case.
Thus, even if the lawyer has done an awful job as trial counsel, it is highly unlikely that a conviction will be reversed if the record shows the government’s evidence was convincing. Moreover, on the question whether the lawyer did a bad job, the defendant’s conduct will be relevant. So if the defendant failed to tell his lawyer the truth about the case or told the lawyer he did not want this or that strategy followed, he won’t be heard to complain about it later, even if it was dumb for the lawyer to follow the client’s instructions.
So you’re right, the first thing does not follow from the second.