A particular dispute arose between the Government of the Irish Free State of the one part and the Northern Ireland and UK governments of the other part over territorial waters in Lough Foyle. Lough Foyle lies between County Londonderry in Northern Ireland and County Donegal in the then Irish Free State. A court case in the Free State in 1923 relating to fishing rights in Lough Foyle held that the Free State's territorial waters ran right up to the shore of County Londonderry. In 1927, illegal fishing on Lough Foyle had become so grave that Northern Ireland Prime Minister James Craig entered into correspondence with his Free State counterpart, W. T. Cosgrave. Craig indicated to Cosgrave that he proposed to introduce a bill giving the Royal Ulster Constabulary powers to stop and search vessels on Lough Foyle. Cosgrave asserted all of Lough Foyle was Free State territory and that as such a bill of that nature would be rejected by the Free State and its introduction would create "a very serious situation". Cosgrave then raised the matter with the British government. Claims by The Honourable The Irish Society that its fishing rights in the Foyle were being violated by poachers from the Donegal side led to the 1952 creation of the Foyle Fisheries Commission under the joint authority of the Dublin and Belfast governments, which solved problems of jurisdiction without addressing the sovereignty question. The commission was superseded by the Foyle, Carlingford and Irish Lights Commission established after the Good Friday Agreement under the remit of the North/South Ministerial Council.
