The exclave was dealt with in nineteenth century legislation as greater administrative duties were given to the counties. The Police (Scotland) Act 1857 established police forces throughout Scotland. A section of the act allowed for the parishes to be transferred to the jurisdiction of either Stirlingshire or Lanarkshire Constabulary on resolution of two thirds of the Commissioners of Supply for the County of Dumbarton. Similar provisions allowing for the transfer of the area for all purposes were included in the County General Assessment (Scotland) Act 1868. No such resolution was made, and the two parishes remained in Dumbartonshire.
The Roads and Bridges (Scotland) Act 1878 provided that for the purposes of that act all detached parts of counties should be placed in the county by which they were surrounded, or with which they had the longest boundary. Accordingly, Cumbernauld and Kirkintilloch came under the control of the Stirlingshire Road Board. It was originally anticipated that the area would be transferred to Stirlingshire for all other purposes by the boundary commissioners proposed by the Local Government Bill of 1889 However, a clause was inserted in the bill that stated "the parishes of Cumbernauld and Kirkintilloch, including the burghs and police burghs situate therein, shall for the purposes of this Act, be considered as forming part of the county of Dumbarton". The clause was vigorously opposed by the Stirlingshire Commissioners of Supply as they had incurred considerable expense in maintaining the roads of the two parishes. The Act as passed provided that the Dunbartonshire County Council was to financially compensate Stirlingshire on the transfer of road powers.
The regional identity was retained for some major functions such as fire service and police at the next reorganisation of local government in 1996, but for most purposes the former county then found itself served by three new unitary councils: Argyll and Bute Council (which took over the Helensburgh and Lomond part of Dumbarton District), West Dunbartonshire Council and East Dunbartonshire Council. Cumbernauld was not included in either of the new Dunbartonshire councils, instead being placed in the North Lanarkshire area.