Interjurisdictional immunity of highly limited application

Marine Services International Ltd. v. Ryan Estate, 2013 SCC 44 effectively eliminates the doctrine of interjurisdictional immunity:

Interjurisdictional immunity exists to protect the "basic, minimum and unassailable content" or the core of the "exclusive classes of subject" created by ss. 91 and 92 of theConstitution Act, 1867: Bell Canada, at p. 839.  This Court discussed interjurisdictional immunity in Canadian Western Bank and later in Quebec (Attorney General) v. Canadian Owners and Pilots Association, 2010 SCC 39, [2010] 2 S.C.R. 536 ("COPA").  The doctrine has a limited application today: Canadian Western Bank, at paras. 33-34. InGeneral Motors of Canada Ltd. v. City National Leasing, [1989] 1 S.C.R. 641, Dickson C.J. stated that the dominant tide of constitutional interpretation, which favours, where possible, the operation of statutes enacted by both levels of government, militates against interjurisdictional immunity.  A broad application of the doctrine is inconsistent with a flexible and pragmatic approach to federalism.  As stated earlier, interjurisdictional immunity "is of limited application and should in general be reserved for situations already covered by precedent": Canadian Western Bank, at para. 77.