§1. Unless particular law provides otherwise, while cases are being heard before the tribunal, only those persons are to be present in court whom the law or the judge has established as necessary to expedite the process.
§2. With appropriate penalties, the judge can call to task all those present at a trial who are gravely lacking in the respect and obedience due the tribunal; furthermore, the judge can also suspend advocates and procurators from the exercise of their function in ecclesiastical tribunals.
Source: Code of Canon Law (Vatican.va)