18y-olds living at home - legal position?

[Number42]

I have in my mind that "the police don't get involved in family arguments". What's the deal if:

• you have an 18 yo child living at home; it's not working out; you say "You need to move out" and they say "I'm not going"?
  

I mean obviously you can do stuff like change the locks when they're out, but if you were to try to involve the police, would they say "Sorry madam we don't get involved in family arguments" or would they in the end apply the same standards as they would any other adult invading your home? This is not a real world question - yet!

[datkins]

unless his name is on the housing contract then your kid has no legal right to live there and therefore police can remove him from the property, but obviously nobody wants that but if it comes to it then you can call them for assistance.