Once he starts to defend her, the Court can make him stay on the case if allowing him to withdraw would prejudice Jodi's ability to be adequately represented at trial, especially if he is receiving sufficient compensation. In other words, if another attorney couldn't be expected to come up to speed in time to do it -- along with other reasons that are within the Court's discretion. I imagine it's especially hard to get off a capital case once you've been lead counsel for the defendant for a significant period of time and the trial date is approaching. Once the trial date is near, it would be next to impossible, imo, if not completely impossible.