At least for the time being, the international community must rely on national courts to prosecute modern-day pirates. The first wave of domestic piracy prosecutions suggests, however, that domestic courts have yet to achieve the necessary consistency and expertise in resolving key questions of international law in these cases. This article evaluates how courts trying modern-day pirates have addressed common questions of international law regarding the exercise of universal jurisdiction, the elements of the crime of piracy, and the principle of nullum crimen sine lege. In doing so, it evaluates five decisions issued in 2010 by courts in Kenya, the Netherlands, the Seychelles and the United States, and it proposes some clear answers to these recurrent questions of international law in domestic piracy prosecutions.