Well, I guess it's like the old chestnut of a car needing to display a tax disc provided that some major part of the vehicle is not missing.... ie, you cant secure a prosecution if a major component is missing as it ceases to be a road going vehicle or, the loophole (prob now closed) of whether the entrance to a car park is shared for in and out traffic or if there are 2 defined routes not shared by in and out traffic effecting the status of that car park as a public highway.

Mind you, I've been out of it for 8 years so my info is prob well out of date...
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