On 06/04/2018 17:06, michael adams wrote:
Because anyone can then park across your "drive" and block you
in. Or out.

If you have a proper access, i.e. a dropped kerb, then you
can complain to the plod if you are blocked in, and they
will threaten the culprit with obstruction.

However, if they block you from entering your property,
then it's a civil matter, plod is not interested.