I hope your partner is not smoking in the van. If he is, he commits a criminal offence. It’s classed as a workplace. You didn’t ask about that but I mention for completeness.
I don’t why the van is parked outside the neighbour as opposed to being parked outside your own property. If there is no restriction on parking, then anybody can park where they like provided it is not across any part of a dropped curb.
The neighbours are harassing him through a3rd party.
Harassment is defined as a course of action (more than once) which is intended to harass, does harass, is reckless as to whether it harasses, or if the average bystander would look at the conduct and think that it was indeed harassment.
Harassment is both a civil matter and a criminal matter.
If you are being harassed. Go to the police and ask them to warn the ex-under the Protection from Harassment Act. Some police forces take that very seriously and others not so and therefore, you may need to speak to a senior officer or put a complaint in writing to the Chief Constable.
He could also apply to the civil court for an injunction to stop this constant harassing.
You may find that a strongly worded letter from a solicitor threatening a court application and an application for costs, may focus the mind without actually the need to get to court.
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