Admiralty courts have discretionary jurisdiction meaning they have discretion over whether or not to exercise their jurisdiction when it is legally proper to do so.  In Koupetoris v. Konkar Intrepid Corp., 402 F. Supp. 951 (S.D.N.Y. 1975), the court held that if there is an alternative forum in which all the sources of proof are available, a federal district court has “unqualified discretion to decline jurisdiction in suits in admiralty between foreigners.” 

The court exercises discretionary jurisdiction when a ship voluntarily enters the territorial limits of a country and subjects itself to that country’s jurisdiction.  Likewise, the court can exercise discretion if the question involved is whether to issue an injunction preventing a state court from proceeding on a claim.

In Akofin v. Jumbo Navigation, N.V., 481 F. Supp. 2d 310 (S.D.N.Y. 2007), the court held that a district court has discretion to dismiss an action under the doctrine of forum non conveniens, even if the law applicable in the alternative forum may be less favorable to the plaintiff’s chance of recovery.  However, an admiralty court will not exercise its discretion to allow the plaintiff’s claim to remain inactive until in rem jurisdiction may be obtained.[i] 

[i] Cevhertas Deniz Nakliyati Anonim Sirketi, A.S. v. Niederelbe Schiffartgesell Gmbh Buxtenude, 1991 U.S. Dist. LEXIS 8746, 23-24 (S.D.N.Y. June 28, 1991)