I would think it depends on the scenario...

If someone broke into your house and snatched a kid I would think you have legal right to do that, however if a mother who was not allowed to see her child snatched her from school I highly doubt the school has any right to shoot her.

*This is not legal advice I am not an attorney for entertainment purposes only*.

Thats my 02.

To broad a question really.

And like Blast said that situation is common even with non-adopted kids