Criminal assault.
So if you saw me pouring Ammonia down a baby's throat in my car, you wouldn't call the cops?
How about Benzine?
Cadmium?
Cyanide?
Insecticide? (DDT,Methoprene
Arsenic?
http://www.quitsmokingsupport.com/whatsinit.htm
I agree that less Government is better. Less intervention is better. But not at the expense of a child's life. The line comes in at defending those that cannot defend themselves.
OR
Intervention now might prevent the kid from being dependent on social welfare programs all of his/her life because mommy and Daddy gave him Emphysema/Asthma/whatever, now he cannot work and you have to pay for it.
Take your pick.
Just my 2cents