the problem is who is to decide what is henious? if you let the goverment decide, you never know what they will brand as henious. to some, murder and child rape are henious. to others, they might want to include child abuse. others (keep in mind, in this country, this is alot of people), may decide that homosexuals shouldnt be allowed to have kids, or that people with a history of drug abuse cant have kids.
we cant have that, because once a precedent has been set, there are not limits to where it can go. one day it's sterilizing murderers, then before you know it two years later people with low I.Qs, druggies, homos, and overly promiscus people will be gettting sterilized.
what WOULD be legitimate, would be this:
if one wishes to have a baby, they must get a license. This is FREE, but the parents must attend classes, pass tests, and have inspections of their households. think of the movie "license to wed". this would also involve community service involving kids (e.g "big brothers" thing, or spending time with a much younger relative could also count), along with backround checks.
If one wishes to Opt out of getting a license, or simply cant pass the test, they may still have kids. exept they would be heavily taxed for every child. the kid would also be inelligible to attend public school, and inelligible for any form of insurance. If one is unable to take care of a child at that point, after taxes and everything, the kid is taken away, and the parents jailed for tax evasion.
this would ensure that if one has kids, they better be able to take care of them. If they seem to think they can, but are really just sheep and fuck their kids up, and cant take care of them, the kids get help and the parents are punished.