Go find a law that gives you the right to take an intruder down in your house or on your premises.
He can stand next to your baby's crib at 3am in the morning...you find him there it's expected of you to open a dialogue in the dark and sing khumbaya
This country is SO catering for "certain people"
TL;DR
If you fire warning shots and the intruders continue to advance towards you, it is classed as self-defense.
Full Version:
It's actually easier than this and information given to me by someone who works in crime forensics.
Put 2 shots into the intruder and then fire 2 shots out the room window or into the wall in quick succession.
When it comes down to investigation, you tell them you fired 2 warning shots into the wall and they advanced towards you, so you defended yourself. When they interview the neighbors, the most they can say is they heard 2 shots and then another 2 shots.
In this way, they have no way of proving whether or not you shot the intruder first or the warning shots first.
Alternatively, invest in a paintball gun and pepper balls, they have like a 2m - 3m spread if they explode on a wall or person.
You have more shots in a paintball gun than you do in a normal 9mm. If you empty a round of pepper balls into them or around them, they not going anywhere and you could probably beat the **** out of them and tie them up and call the police.