IV § 8 Supplemental Briefs

If you want to file an extra brief in your case, whether it's about the main issues or about a motion, you can generally do that at any time. This gives you some flexibility if new information comes up or you need to add to your arguments.

But there's an important limit. Once your case has already been argued in court or submitted to the judges for a decision, you can't just file a new brief on your own. At that point, you need to ask the court for permission first. If you file one without asking, the court won't consider it.

The takeaway here is timing matters. If you have something to add, do it before your case gets argued or submitted. Waiting until after that point means you'll need the court's permission, and there's no guarantee they'll grant it.