At the time of the deposition, all co-defendants should be cooperating with each other. Even if you think one of your co-defendants committed malpractice, this is not the time to mention that fact. Keep that information to yourself until backed into a corner where you have no choice but to reveal that. Why? You don’t want to help the plaintiff’s case at all.
You might think that revealing this information might get you out of the case leaving only the “true guilty party.” Wrong. Turning on your co-defendant won’t help you get out of the case. In fact, it will likely ensure your staying in the case because your co-defendants’ finger will now be pointing directly at you. Thus, you will fall into the trap set by the plaintiff’s attorney; sue everybody in sight and have them turn against each other so as to get money from at least one of you.
Her blog looks pretty interesting.