The court went on to state that there was "no compelling reason to hold otherwise," and "[i]f a defendant in an admiralty action
Clearly the Court was trying to harmonize earlier decisions (41) that appeared to categorically bar in rem admiralty actions involving a res (a vessel or cargo) under claim by the federal government, with a more "liberal" rule that permitted such arrests and actions to proceed when the actual possession of the government over the property was not being "disturb[ed]" or "invaded.
In considering whether the Eleventh Amendment applies where the State asserts a claim in admiralty to a res not in its possession, this Court's decisions in cases involving the sovereign immunity of the Federal Government in in rein admiralty actions provide guidance, for this Court has recognized a correlation between sovereign immunity principles applicable to States and the Federal Government .
119) Despite proceeding in personam, there are still some significant in rem implications for FSIA admiralty actions.
Perhaps predictably, Lord Steyn's remarks about the nature of the admiralty action in rem ignited something of a firestorm amongst maritime law commentators.
The link between Roman law and the modern in rem admiralty action is equally suspect: see William Tetley, 'Arrest, Attachment and Related Maritime Law Procedures' (1999) 73 Tulane Law Review 1895, 1900; but cf Michael Jonsson 'The Nature of the Action In Rem' (2001) 75 Australian Law Journal 105, 105-106.
61) See generally, Nigel Teare, 'The Admiralty Action In Rem and the House of Lords'  Lloyd's Maritime and Commercial Law Quarterly 33; BJ Davenport, 'End of an Old Admiralty Belief' (1998) 114 Law Quarterly Review 169; Derrington, above n 60; Sarah C Derrington and James M Turner The Law and Practice of Admiralty Matters (Oxford University Press, Oxford, 2007) Ch 2; Comandate Marine -.
53) This fact is significant to note in understanding the Court's final decision and in understanding the scope of sovereign immunity in admiralty actions.
The federal court's jurisdiction over admiralty actions is not exclusive.
Because Northern involves an in personam admiralty action, the scope of sovereign immunity with respect to in rem admiralty issues is not at issue.