ALAN BLEASDALE, dramatist: I have in the past. A boy of 16 shot my son in the back of the head with an air pistol. Before I knew it, I grabbed the lad and the gun and dragged him all the way home to his mother. My foot met his backside several times and I smashed the gun to pieces. I understand why people take the law into their own hands, but I wouldn't advise it. We live in bleak and vile times and in different circumstances I could have come off worse than my son did.

FATIMA WHITBREAD, athlete: I might if I saw a child or old person being abused. But I wouldn't if someone was damaging a bollard. That's the responsibility of the council.

PETER HONEY, psychologist: It's crazy to take on a gang of people single-handed. It's a risk not worth taking.

ALFIE WEAVER, minder: Yes, if I were defending my home or my children. But I would make sure whoever it was hit me first so I couldn't be done for GBH]

DENNIS SKINNER MP: I've done it. Hell] I was brought up in a mining village where you'd be expected to take action. For people with a bit of red blood in their veins it's only natural.

ROSS KEMP alias GRANT in EastEnders: I once saw an old lady being duffed up in a car, so I opened the door to help her, and she just told me to 'F*** off' - very neighbourly]

ANNA BARRINGTON, archaeologist: I was once attacked on the Tube by a man sitting opposite me who swung up on the handles and landed on my legs. I screamed but everyone just popped their newspapers up. Of course I'd have a go if I could.

JOHN STALKER, former policeman: If it was two tattooed football fans rolling around I'd just let them get on with it, but if it was a woman of course I'd get involved. I'd probably be halfway in before I remembered I wasn't still in the Force.

LYNSEY DE PAUL, singer/songwriter and self-defence writer: I'm a bit like a terrier taking on an alsatian. The first time was when I saw this thug bashing the head of an old man against the railings near Highgate Cemetery. I drove straight onto the pavement and screamed, 'Leave him alone', and then I pushed open the back door and shouted to the old man, 'Quick, get in the car,' and we shot off down the street.

(Photograph omitted)