Originally Posted by
Section 107
I think one should be not at all surprised at, nor doubting of, robust levels of data communication and coordination between the domestic security (including border security) and intelligence agencies and services of the yanks, their cousins and the 51st state, especially between CA and the GB as they are part of the same (if crumbling) commonwealth.
I'm pretty sure that UK doesn't commonly stop -- let alone care to check -- the Canadian or US criminal history of most Canadians visiting the UK without a visa.
The data sharing is relatively stove piped to say the least. And with the rare sort of exceptions that I've noted above in this thread, the impact when say flying YYZ-LHR is limited.