Breeding unicorns
Getting gov depts to share data has been a Whitehall wet dream for years and everytime someone tries it, it crashes and burns from the withering fire of "who controls what" guns (data, servers, security on servers, yada yada). And if a dept gives up its data, then who needs that dept anymore... Job cuts, JOB CUTS!! Civil servants are well versed in the dark arts of protectng their pensións, so cat in hell's chance even for sCummings.