When the good is bad

See ! I specifically warned against do-gooders. Atanu makes the same point.

To repeat what Atanu already said, child labour is an economic problem (as is poverty), legislation can not solve it.

In fact I would like to go further and argue even social problems can not be solved with legislation. People who clamour for legislation against dowry, or sex-selection tend to assume that state which is going to enforce legislation is something distinct from society. This is erroneous to say the least. Bureaucracy is not isolated from society and the rot in society will find its way in any institution meant for administration, pious intentions notwithstanding.
The problem in fact becomes worse because any such legislation will vest the state and bureaucracy with more power with increasing prospect of corruption.

Here I concede there is a major weakness in my argument, because there are very few problems which are not social in nature. The state can not be done away with, and it is a problem when watchdogs are themselves stealing hens.
A tentative solution is, in addition to restricting the power of state, we must ensure that
1. No part of society is powerful enough to oppress other.
2. No part of society is powerless enough to resist oppression.

This demands multiplicity of strategies from economic prosperity and independence to social movements which unify the victims, giving them voice (and may be in some rare cases even legislation).