Residents refusing to let my son park

We currently have the council on our street so a vast majority of the street is coned off, parking was always volatile but this as made the situation and tensions rise alot further. Due to issues regarding a broken down car that cannot be moved at the moment this particular neighbour as now involved 2 other residents on the other side of the street who don’t have cars themselves and its also where my son as parked for 2 years, they are now coming up with obvious untrue reasons as to why my son can’t park there, its a public road, his car is taxed and insured, can they dictate who can park, he causes no obvious problem, no obstruction and was courteous enough to ask in the first place Any advice would be appreciated