I’m not asking about the ethics of lying, or whether lawyers may be justified in lying. That is beside the point. I am just asking: hypothetically, would it be possible for a lawyer to have a successful career while never uttering so much as a white lie?
Like, let’s say the lawyer had some sort of spell cast on them, so they could never lie. If someone were to ask them a question, they’d either need to find a way to avoid answering or answer honestly. Would it be possible for a lawyer in such circumstances to still go on and have a successful career?


Of course.
First, lawyers don’t say “my client is innocent”. They say “my client claims he is innocent”. Lawyers are not witnesses, they don’t claim anything in the court. They present evidence and ask questions. You don’t have to lie to do it.
Second, people imagine the job of a lawyer is to get their client acquitted. It’s not, it’s to represent their client in court.
Let’s say you are a lawyer and you have to represent a serial killer. The evidence is overwhelming and it’s obvious he is guilty but still he pleads “not guilty”. Your job is not to try avoid conviction. Your job is to make sure he is treated fairly and that his rights are respected. You basically have to oversee the trial from his side. Make sure that evidence was obtained legally, that witnesses tell the truth, that experts have proper credentials. You don’t have to lie to do any of that.
Yes, some lawyers will be experts in taking out criminals out of jails by manipulating juries, forging evidence or intimidating witnesses. Most lawyers are not.