Which action is prohibited by a lawyer under the duty of decorum to the tribunal?

In the context of a lawyer's duty of decorum to the tribunal, the prohibition against certain actions is critical to maintaining the integrity of the legal process and ensuring that proceedings are conducted fairly and orderly. Each of the actions listed violates this duty.

Communicating ex parte with jurors during proceedings undermines the impartiality of the jury, which is a cornerstone of a fair trial. This type of communication can lead to bias or an unfair advantage, directly impacting the justice system's function.

Seeking to influence the decisions of judges also breaches this duty. Lawyers must not engage in behaviors that attempt to sway judicial outcomes through improper means, as this compromises the independence of the judiciary and the rule of law.

Engaging in conduct that disrupts court proceedings is another clear violation of decorum. Disruptive behavior hinders the court’s ability to function properly and can negatively affect both the proceedings and the participants involved.

Thus, all these actions contravene the standards of professionalism and respect that lawyers are required to uphold in court, making the comprehensive answer that all of the options represent prohibited actions under the duty of decorum to the tribunal.