Whenever a complaint shall be made against any master, officer, or seaman of any vessel belonging, in whole or in part, to any citizen of the United States, of the commission of any offense, not capital or otherwise infamous, against any law of the United States made for the protection of persons or property engaged in commerce or navigation, it shall be the duty of the United States attorney to investigate the same, and the general nature thereof, and if, in his opinion, the case is such as should be summarily tried, he shall report the same to the district judge, and the judge shall forthwith, or as soon as the ordinary business of the court will permit, proceed to try the cause, and for that purpose may, if necessary, hold a special session of the court, either in term time or vacation.

At the summary trial of offenses against the laws for the protection of persons or property engaged in commerce or navigation, it shall not be necessary that the accused shall have been previously indicted, but a statement of complaint, verified by oath in writing, shall be presented to the court, setting out the offense in such manner as clearly to apprise the accused of the character of the offense complained of, and to enable him to answer the complaint. The complaint or statement shall be read to the accused, who may plead to or answer the same, or make a counterstatement. The trial shall thereupon be proceeded with in a summary manner, and the case shall be decided by the court, unless, at the time for pleading or answering, the accused shall demand a jury, in which case the trial shall be upon the complaint and plea of not guilty.

It shall be lawful for the court to allow the United States attorney to amend his statement of complaint at any stage of the proceedings, before verdict, if, in the opinion of the court, such amendment will work no injustice to the accused; and if it appears to the court that the accused is unprepared to meet the charge as amended, and that an adjournment of the cause will promote the ends of justice, such adjournment shall be made, until a further day, to be fixed by the court.

At the trial in summary cases, if by jury, the United States and the accused shall each be entitled to three peremptory challenges. Challenges for cause, in such cases, shall be tried by the court without the aid of triers.

It shall not be lawful for the court to sentence any person convicted in such trial to any greater punishment than imprisonment in jail for one year, or to a fine exceeding $500, or both, in its discretion, in those cases where the laws of the United States authorize such imprisonment and fine.

All the penalties and forfeitures which may be incurred for offenses against title 48 of the Revised Statutes may be sued for, prosecuted, and recovered in such court, and be disposed of in such manner, as any penalties and forfeitures which may be incurred for offenses against the laws relating to the collection of duties, except when otherwise expressly prescribed.