My main rule, and one which my children follow is lawful and within the realm of responsible parenting.

I simply instruct them to say "My mother told me never to talk to strangers".

Is this not what we teach our children? To never talk to strangers?

If my children don't want to talk to any DoCS workers, or they suspect someone who wants to speak with them is associated with DoCS - this is what they tell them.

This brilliant insight actually worked for me and frustrated the daylights out of DoCS workers in early 2006 who went to my childrens' school to talk to them. My children wouldn't even tell them what they had had for lunch.

The DoCS workers came back to my house afterwards and commended me for instructing my children to say what they said. It was laughable - DoCS couldn't do a thing about it and putting it in an affidavit would have made them look stupid.