New Haven criminal defense attorney John Williams faces a 20-day suspension for “willfully” violating a judge’s order during a criminal trial that ended in his client’s conviction.

The suspension starts Jan. 15, unless Williams decides to appeal Superior Court Judge Jon Blue’s decision, which would stay the order until the resolution of the appeal. Last week, Williams said he felt “profound regret” that during proceedings for his client, convicted arsonist Angelo Reyes, he twice violated Blue’s order to not disclose to a state jury that his client had been acquitted of charges in a federal trial. The revelations came once during cross-examination of a witness and a second time during closing arguments.