In October 2021 the US Supreme Court ruled in New York State Rife & Pistol Association, Inc., v Bruen, Superintendent of New York State Police that a citizen may possess a firearm without the necessity of proving they have a special need for self-protection distinguishable from the general community. The reasoning behind the opinion relied upon historical tradition of firearm regulations. In so ruling the court rejected prior cases that required a two part analysis whether a statute was constitutional. The prior law required the court to interpret a second amendment issue by first looking to the historical context of the Second Amendment. This means the court looks to what persons could legally possess a firearm at the time the amendment was enacted. There is very good discussion on this element in cases that have issued opinions on the history since Bruen was handed down. The court did away with the second part of the analysis (means-end scrutiny). So currently one may argue that when the Second Amendment was enacted (1791) there was no general prohibition for a convicted felon from possessing a weapon.
Most courts have decided against a felon possessing a weapon since Bruen. However, there are some opinions that are very informative on this issue. I believe, even if the client does not prevail at the trial court level on a motion to dismiss, that a motion should be filed to preserve the issue on appeal.