To clear the grey area and doubt on this matter. It is the owners right to defend anybody or thing on it. The law should be in favour of the property owner.
The law should be tightened up about unwanted people on your property. You have the right under any circumstance to defend & protect your property and anybody on it that you consent to. Anybody going on to private property does so at thier own risk.
Why should you have to think if your actions will be within the law when you are being threatened or intimidated?
I know I wouldn't hesitate if my family or property were at risk.