Art. 561 Change of plea of "not guilty" to "not guilty and not guilty by reason of insanity"

If you plead "not guilty" to a crime, you have 10 days after your arraignment to change that plea to "not guilty and not guilty by reason of insanity." This gives you a chance to raise an insanity defense even after your first plea.

After those 10 days pass, you can still ask the court to change your plea, but you'll need to show a good reason why you're asking late. The judge has to approve this change, and it must happen before your trial actually starts. Once the trial begins, this option is no longer available.